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Kerala Agricultural University, Thrissur
The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively.
Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively.
On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs.
In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc.
During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU).
Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.
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ThesisItem Open Access Customized fertilizer and nutrient scheduling for okra (abelmoschus esculentus (L.) moench)(Department of Agronomy, College of Horticulture, Vellanikkara, 2016) Yansin, Luikham; KAU; Anitha, SMultinutrient deficiencies in soil are common nowadays due to imbalanced use and extensive mining of nutrients, which have also led to the decline of soil and crop productivity over time. Customized fertilizers (CF), which are multinutrient carriers facilitating the supply of complete range of nutrients in right proportion for the crop grown in a particular soil, have come up as an alternative to tide over these problems. Scheduling of nutrients by split application promotes efficient utilization of nutrients in a need based manner and helps to reduce nutrient losses from the soil. An investigation entitled “customized fertilizer and nutrient scheduling for okra (Abelmoschus esculentus (L.) Moench)” was carried out at the Water Management Research Unit, Vellanikkara, Thrissur from May to September, 2015 with the objective of developing a customized fertilizer and studying its techno- economic feasibility and nutrient scheduling in okra. The investigation consisted of 12 treatments viz., FYM + 75% CF (2 splits at 30 days interval), FYM + 75% CF (4 splits at 15 days interval), FYM + 100% CF (2 splits at 30 days interval), FYM + 100% CF (4 splits at 15 days interval), FYM + 125% CF (2 splits at 30 days interval), FYM + 125% CF (4 splits at 15 days interval), FYM + soil test based NPK application (N & K as 2 splits at 30 days interval), FYM + soil test based NPK application (N & K as 4 splits at 15 days interval), FYM + NPK as per POP (N & K as 2 splits at 30 days interval), FYM + NPK as per POP (N & K as 4 splits at 15 days interval), FYM alone based on N recommendation of POP (2 splits at 30 days interval) and absolute control. Biometric observations were recorded and nutrient contents and uptake were estimated at 30 DAS, 60 DAS and 90 DAS. A customized fertilizer grade was developed based on the initial analysis of macro and micronutrient contents of soil and nutrient requirement of okra. Water soluble fertilizers and straight fertilizers were used for the preparation of CF. Based on the soil fertility rating and nutrient recommendation for okra, the actual nutrients needed for the experimental site was worked out in kg ha-1 as 59N: 9P: 34K: 16Mg: 1B. Based on this, CF grade 22.01N: 3.35 P: 12.68K: 5.97Mg: 0.37B was developed. The study revealed that application of 125 per cent CF either as two or four splits was equally effective and recorded the highest yield compared to lower doses of CF and other nutrient management practices. Application of 125 per cent CF resulted in a yield increase of 32.11 per cent, 35.16 per cent and 49.84 per cent compared to soil test based application, application of nutrients at recommended dose and application of FYM alone respectively. Application of 100 per cent CF recorded higher yield compared to nutrient application based on soil test based NPK and NPK as per POP. The yield increase in 125 per cent CF was due to the better development of growth and yield parameters and higher nutrient uptake including that of Mg and B in customized fertilizer doses. The lower doses of CF (75%) performed equally well as soil test based NPK and NPK as per POP with respect to yield. The combined application of fertilizers along with FYM gave better yield than application of FYM alone as a source of nutrients. Faster delivery of nutrients could be achieved through fertilizers since FYM alone could not meet the huge requirement of nutrients by okra. In this study, application of CF and other fertilizers in more splits did not show significant increase in yield of okra. Application of CF showed a positive effect on the soil fertility status except for nitrogen. The improvement in nutrient status could be attributed to application of optimum dose of CF along with FYM to maintain adequate supply of nutrients. The application of higher levels of CF was cost effective and economically beneficial due to higher yield despite increased cost of cultivation owing to higher cost of inputs. Nutrient application in lower splits was more economical due to reduced labour. The study indicated that application of multinutrient carriers such as customized fertilizers are a technologically and economically viable practice for increasing soil and crop productivity. The quantities of NPK required as CF are much lower than the POP recommendations, and therefore fertilizer doses can be reduced substantially.ThesisItem Open Access Standardisation of nutrient and weed management techniques for organic rice(Department of Agronomy, College of Agriculture, Vellayani, 2013) Murugesh, M S; KAU; Girija Devi, LThe present investigation on “Standardisation of nutrient and weed management techniques for organic rice” was conducted at the Department of Agronomy, College of Agriculture, Vellayani, during 2012-2013. The objectives were to standardise the nutrient schedule, spacing and weed management techniques for organic rice and to assess the economic feasibility of the organic package. The experiment was laid out in the field in split plot design with combination of spacing, S (S1-20 cm x 15 cm and S2-15 cm x 15 cm) and weed management techniques, W (W1-stale seedbed and W2-hand weeding) as main plot treatments and nutrient schedule, N (N1-option-1 of the ad hoc recommendation of KAU: FYM 5 t + 800 kg oil cakes ha-1 (1/2 basal + 1/2 top dressing at active tillering stage), N2-option-2 of the ad hoc recommendation of KAU: FYM 1 t + green leaf manure 1t + dual culture of azolla + 2 kg Azospirillum + 2 kg P solubilizing bacteria + 1kg PGPR (mix 1) ha-1, N3-option-3 of the ad hoc recommendation of KAU: 1/3rd RDN as FYM, 1/3rd as vermicompost and 1/3rd as neem cake + 2 kg Azospirillum + 2 kg P solubilizing bacteria ha-1, N4-soil test based application–half as vermicompost and half as neem cake). The KAU Package of Practices Recommendation (FYM 5 t + 90:45:45 kg NPK ha -1) was taken as control. Closer spacing (S2-15cm x 15 cm), hand weeding (W2) and option-3 of the ad hoc recommendation of KAU (N3) significantly influenced plant height and DMP, while closer spacing (S2-15cm x 15 cm) and option-3 of the ad hoc recommendation of KAU (N3) only had significant influence on tiller production and LAI. Stale seedbed (W1) and closer spacing (S2-15 cm x 15 cm) had significant influence on most of the yield attributing characters, while, among nutrient schedule, N3 (option-3 of the ad hoc recommendation of KAU) attributed the maximum for yield contributing characters, but was on par with N4 (soil test based application) and also with N1 (option-1 of the ad hoc recommendation of KAU) for grain yield. The results on weed control revealed the superiority of closer spacing (S2-15 cm x 15 cm) and stale seedbed technique (W1) over others in controlling the weeds throughout the growth stages. However the weed control efficiency was the lowest in conventional (Control-KAU Package of Practices Recommendation) compared to the organic throughout the growth stages. The nutrient uptake was the highest in N3 (option-3 of the ad hoc recommendation of KAU) and the lowest in N2 (option-2 of the ad hoc recommendation of KAU). However, uptake study had also revealed the superiority of conventional (Control-KAU Package of Practices Recommendation) over organic in the uptake of nutrients. The net returns and B:C ratio were the highest in closely spaced plants (S2-15 cm x 15 cm) and in N3 (option-3 of the ad hoc recommendation of KAU). From the study it can be concluded that for realising higher grain yield in organic rice, a closer spacing of 15 cm x 15 cm (S2) is ideal. Any of the two weed management techniques, i.e., either stale seedbed (W1) or hand weeding (W2) can be practiced for controlling weeds. Option-3 of the ad hoc recommendation of KAU (N3-1/3rd RDN as FYM, 1/3rd as vermicompost and 1/3rd as neem cake + 2 kg Azospirillum + 2 kg P solubilizing bacteria ha-1) is the best nutrient schedule for realizing maximum yield from organic rice. The most economic package for organic rice production is the combination of closer spacing of 15 cm x 15 cm (S2), with stale seedbed technique (W1) of weed control and option-3 of the ad hoc recommendation of KAU (N3-1/3rd RDN as FYM, 1/3rd as vermicompost and1/3rd as neem cake + 2 Kg Azospirillum + 2 Kg P solubilizing bacteria ha-1) as nutrient schedule. The organic package was economically significantly superior to conventional package due to the premium price fetched by organic rice.ThesisItem Open Access Nutrient Management for yield and quality improvement in Kacholam(Department of Agronomy, College of Horticulture, Vellanikkara, 2012) Kavitha, P R; KAU; Meera, Menon VKacholam (Kaempferia galanga L.) is an important medicinal and aromatic plant of the Zingiberaceae family. In India, kacholam is cultivated throughout the plains for the rhizomes. The economic produce of kacholam is the chopped and dried rhizomes of 6-7 months maturity. Dried rhizomes are used in bulk quantities in ayurvedic medicine and in the cosmetic industry. It is used for curing inflammatory wounds, skin disorders, piles, oedema, fever, epilepsy, splenic disorders and asthma. The constituents of the rhizome oil include para methoxy ethyl cinnamate (60.24 % of the oil), ethyl cinnamate (20.66%), cineol, borneol, 3-carene, camphene, kaempferol, kaempferide and cinnamaldehyde. There is immense scope for cultivation of kacholam in Kerala, as the climatic and soil conditions are optimally suited to its growth and development. Kacholam can be grown as an intercrop in coconut gardens and it has attained the status of a cash crop of homesteads. Though there is an approved ad hoc recommendation of organic manures as well as N, P and K for kacholam, there are reports that the K dose is inadequate. Also, considering the low availability and high cost, the present organic manure recommendation of 20 tonnes ha-1 is rather unaffordable. There are also reports about the inadequacy in the availability of secondary nutrients viz., S, Ca and Mg, which may affect yield and quality of kacholam. A field experiment was conducted during 2011-2012 in the coconut garden of Water Management Research Unit, Vellanikkara to evaluate the effect of varying doses of K and secondary nutrients on yield and quality of kacholam. There were 12 treatments with 3 replications each. Treatments consisted of package of practices (POP) recommendation of 20 tonnes farmyard manure along with 50:50:50 kg N, P and K ha-1 and combinations with S, Ca, Mg and extra dose of K applied as first and second top dressing. Rhizomes were planted at a spacing of 20 x 15 cm and planting was done on 3/ 06/ 2011. Harvesting was done seven months after planting. Observations included biometric observations taken at monthly intervals, nutrient contents at 2 ½ and 5 months after planting, and at harvest. Nutrient uptakes was also worked out. Essential oil and oleoresin in rhizomes were also analysed. The soil pH and chemical parameters were analysed before and after the experiment. There were significant differences among treatments with respect to yield, essential oil, oleoresin, nutrient contents and nutrient uptake. With respect to yield, the treatment receiving S applied either at first top dressing or at second top dressing and that with S, Ca and Mg recorded highest yields as compared to other treatments. Essential oil content also showed the same trend as that of yield. But in case of oleoresin, the content was more only in the treatments receiving S as first and second top dressing. This treatment resulted in highest uptake of all nutrients except Ca at harvest. Application of the secondary nutrients thus had a direct positive effect on yield and quality. Changing the N:K ratio of present NPK recommendation resulted in reduction of yield and other quality parameters. The yield and quality parameters with the reduced organic manure dose were found similar to the present POP. Increased phosphorus content of soil observed after experimentation indicated the possibility of reducing the recommended phosphorus dose. Supplementing S, Ca and Mg with a reduced organic manure dose is also to be tested.ThesisItem Open Access Standardization of organic nutrient schedule for chilli (Capsicum annuam)(Department of Agronomy, College of Agriculture, Vellayani, 2013) Akshay; KAU; Sajitha Rani, TThe research project entitled ‘Standardization of organic nutrient schedule for chilli (Capsicum annuum)’ was conducted at Instructional Farm attached to the College of Agriculture, Vellayani during the kharif season of 2012 to standardize the organic nutrient schedule for chilli and to work out the economics. The investigation was laid out as factorial experiment in Randomized Block Design (RBD) with three replications. The treatments consisted of three levels of FYM - F1 (20 t ha-1), F2 (15 t ha-1) and F3 (10 t ha-1) and three levels of substitution of the recommended dose of nitrogen. The levels of substitution are N1 (100 % recommended dose of N- 75 kg ha-1), N2 (75 % recommended dose of N -56.25 kg ha-1) and N3 (50 % recommended dose of N - 37.5 kg ha-1). FYM along with neem cake in 1: 1 ratio is used as organic manure for N substitution. Three controls were also tested in this study. Thèse controls are C1 (KAU POP recommendation -.FYM@ 25 t ha-1 along with75:40:25 kg N:P2O5:K20 ha-1 as inorganic fertilizer), C2 ( KAU Adhoc organic POP recommendation -FYM @25 t ha-1 + Poultry manure at 5 t ha-1 + Pseudomonas + Trichoderma and PGPR mix 1, each @2.5 kg ha-1) and C3 (Farmers practice - Cow dung slurry @ 20 t ha-1) Result of the study revealed that FYM @ 20 t ha-1 recorded significantly higher plant height, no of branches & LAI. The maximum value for all growth parameters were observed at 100% level of N substitution .Combined application of FYM @ 20 t ha-1 along with 100% substitution of recommended dose of N (75 kg ha-1) in organic form registered maximum plant height, branches, LAI, and root spread .This treatment was on par with KAU POP and Adhoc organic POP Maximum yield was recorede at the highest level of FYM (20 t ha-1). Yield contributing characters were also significantly higher at this level. Among the levels of substitution 100% substitution recorded maximum productivity. Application of FYM @ 20 t ha-1 along with 100 % recommended dose of N (75 kg ha-1) as organic form gave maximum productivity which was on par with the yield realized from KAU Adhoc organic POP and KAU POP. Highest level of FYM @ 20 t ha-1 and 100 % substitution of recommended dose of N recorded maximum ascorbic acid, capsaicin content and shelf life. FYM @ 20 t ha-1 along with 100% of substitution of N as organic recorded maximum capsaicin content which was on par with KAU POP recommendation. Ad hoc organic POP recommendation of KAU recorded maximum ascorbic acid content. KAU POP recommendation registered significantly higher N and K uptake than other treatments. Adhoc organic POP recommendations of KAU recorded highest soil pH and organic carbon content. Available nitrogen status of soil was significantly higher in Adhoc organic POP recommendations of KAU but P and K status were on par to KAU POP. Highest B:C ratio and net income were realized in KAU POP. Best nutrient schedules for realising maximum yield from organic chilli is 1) FYM @20 t ha-1 along with 75kg N ha -1 applied through a combination of FYM and neem cake in 1 : 1 ratio + Pseudomonas + Trichoderma and PGPR mix 1, each @2.5 kg ha-1 and 2) Adhoc POP recommendation of KAU -FYM @ 25 t ha-1 along with poultry manure @ 5 t ha-1 + Pseudomonas+Trichoderma and PGPR mix 1, each @2.5 kg ha-1. Economic nutrient schedule for organic chilli is application of FYM @ 25 t ha-1 along with poultry manure @ 5 t ha-1 + Pseudomonas + Trichoderma and PGPR mix 1, each @2.5 kThesisItem Open Access Production potential of cereal fodder crops under various tillage practices in rice fallows.(Department of Agronomy, College of Horticulture, Vellanikkara, 2011) Gintu, George; KAU; Prameela, PIn order to test the feasibility of raising cereal fodders in rice fallows under various tillage systems an experiment entitled “Production potential of cereal fodder crops under various tillage practices in rice fallows” was conducted at the Department of Agronomy, College of Horticulture, Vellanikkara, Thrissur, Kerala. The experiment was laid out in split plot design with four replications during the period from November 2009 to February 2010. The main plots had tillage practices as treatments which included zero tillage with and without herbicide application (M1 and M2), minimum tillage (M3) and normal tillage (M4). The subplots had three treatments, viz., fodder cereals; maize (S1), sorghum (S2) and bajra (S3). Analysis of data on herbage yield of the three fodders under different tillage practices showed that the herbicide based zero tillage, minimum tillage and normal tillage practices resulted in comparable yields (20.72, 18.72 and 18.08 t/ha). Zero tillage without herbicide application resulted in significantly lower yield (11.69 t/ha). Growth parameters like plant height, leaf area index, leaf stem ratio, shoot root ratio etc. recorded at various growth stages also showed the favourable influence of minimum and herbicide based zero tillage on plant growth. Among the cereal fodders, maize recorded significantly higher yield of 20.19 t/ha followed by sorghum with 15.91 t/ha and bajra with 15.81 t/ha. Considering tillage practices and crops together, the highest B: C ratio of 3.31 was realized when maize was grown under herbicide based zero tillage closely followed by maize under minimum tillage with a B: C ratio of 3.24. Of the other two crops, bajra was found to be more profitable than sorghum. Like maize, herbicide based zero tillage resulted in a higher B: C ratio (3.0) for bajra than other tillage treatments. The yield reduction in zero tillage without herbicide application was mainly due to weeds. A study of weed spectrum showed that dicots were the major weed flora followed by grasses and sedges. The weed population and weed dry matter production were the highest in zero tillage without herbicide application followed by minimum and herbicide based tillage and the least was in normal tillage. Weed dry matter production in zero tilled without herbicide plot was 1545 kg/ha compared to a much lower dry matter accumulation of 193 kg/ha in normal tillage plot. The silage made from all the three cereal fodders was found to be of good quality with golden yellow colour, pleasant smell and a pH ranging from 3.8 to 4.2. In silage prepared without the addition of molasses, pH was found to be slightly higher (4.2) compared to silage prepared with molasses as additive (3.9). The study revealed that fodder maize under herbicide based zero tillage was the best with regard to yield and B: C ratio. However, for a herbicide free production system, maize grown under minimum tillage is preferred due to its equally good performance.ThesisItem Open Access Production, characterisation and quality assessment of biochar(Department of Agronomy, College of Horticulture, Vellanikkara, 2015) Ammu Punnoose, KAU; Anitha, SCrop residues in fields can cause considerable crop management problems if they accumulate. Composting is a viable option for crop residue management. However composting of plant twigs and woody plant residues is difficult as they take longer time for decomposition. Conversion of crop residue biomass into biochar and using it as a soil amendment is a nascent approach and then suggested as an alternative to composting and crop residue burning. Biochar is produced by controlled burning of biomass with little or no oxygen, known as pyrolysis. Research information on biochar in agricultural use in India is scanty. Very few reports are available on production, characterization and use of biochar as soil amendment. The present study was proposed against this backdrop to produce biochar from crop residues and to study the effect of biochar on the performance of crops. The investigation entitled ‘Production characterisation and quality assessment of biochar’ was conducted to assess the effect of production methods and materials used on the character of biochar and to study its suitability as soil amendment for amaranth. Woody wild growth, coconut petiole and herbal waste residues left after composting were the three materials used for biochar production. Biochar was produced using heap and drum methods. Biochar was characterised by percentage mass recovery and by physical and chemical distinctiveness. Methods of production and materials used had significant influence on the characteristics of biochar. Drum method gave higher biochar recovery compared to heap method. Porosity, water holding capacity and carbon content were higher in biochar produced from woody wild growth. All biochars showed alkaline pH with the highest pH in coconut petiole biochar. An increase in NPK content was noticed in biochar compared to the materials used. A pot culture experiment was conducted to study the soil amendment effect of biochar on crop performance. The treatments consisted of six biochars produced from three materials using two methods of production, along with three levels of fertilizers ie, 100 per cent recommended NPK, 75 per cent NPK and absolute control( without any fertilizers). Biochar materials were mixed at a 1:1 ratio on volume basis with soil and assessed their effect on the growth and yield of amaranth. They were also compared with treatment of ordinary potting mixture receiving FYM and 100 per cent NPK. A residual crop was raised in the same pot after the experiment and the yield of the crop was noted. For the first crop, the highest yield was obtained in the ordinary potting mixture which received 100 per cent NPK when compared with the biochar treatments. For the second crop, the highest yield was observed in the woody wild growth biochar receiving 100 per cent NPK. This indicated the nutrient retention property of biochar and its long term benefit. Biochar from woody wild growth recorded the highest carbon content, porosity and water holding capacity and produced better yields, among the different biochar materials. Biochar along with 100 per cent NPK recorded the highest yield compared to biochar treatments without fertilizers. Because of the high water holding capacity of biochar, irrigation could be given to the crops once in three days for the biochar applied treatments instead of twice daily as was done in ordinary potting mixture. Increase in pH of the soil was noticed after the experiment indicating its efficiency as a soil amendment in acidic soil. Beneficial properties of biochar like high carbon content, alkaline pH and high water and nutrient holding capacity revealed the suitability of biochar as a soil amendment.ThesisItem Open Access Herbicide mixtures for weed management(Department of Agronomy,College of Agriculture, Vellayani, 2016) Sheeja, K Raj; KAU; Elizabeth, K SyriacThe experiment entitled "Herbicide mixtures for weed management in direct seeded puddled rice Oryza saliva L." was carried out at College of Agriculture, Vellayani, during the period from 2013 - 2016, to assess the bioefficacy of two post emergence herbicide mixtures viz., bispyribac sodium + metamifop and penoxsulam + cyhalofop butyl in direct seeded rice; to study the residual effect in soil; to investigate the impact on microbial and earth worm population, soil enzyme activity and weed seed bank and also to assess the in vitro sensitivity to soil borne pathogen, Rhizoctonia solani, bio control agents and bio fertilizer organisms. Field experiment was undertaken during first and second crop seasons of 2014-15 at Nemom block at farmer's field. The experiment was laid out in RED with 12 treatments and three replications. Bispyribac sodium + metamifop @ 60, 70, 80 and 90 g ha"*,penoxsulam + cyhalofop butyl @ 120, 125, 130 and 135 g ha"*, bispyribac sodium @ 25 g ha"', penoxsulam @ 22.5 g ha"', hand weeding twice and weedy check constituted the treatments. The higher three tested doses of penoxsulam + cyhalofop butyl v/z.,125, 130 and 135 g ha ' and the highest tested dose of bispyribac sodium + metamifop viz., 90 g ha"' were better than other weed management treatments in improving the growth and yield attributes of rice. Pooled analysis indicated the superiority of penoxsulam + cyhalofop butyl @ 135 g ha"' which recorded the highest grain yield (8463 kg ha ' ) and it was statistically on par with its lower doses (130 and 125 g ha*'). Straw yield was not significantly influenced by the weed control treatments. Penoxsulam + c^lofop butyl @ 135 g ha"' recorded the highest net returns (93744 ha *) and B: C ratio (2.43), which was on par with its lower dose (130 g ha"'). Penoxsulam + cyhalofop butyl @ 135 g ha"' was more effective in reducing the total density of weeds. With regard to the control of sedges and BLW, penoxsulam + cyhalofop butyl was more effective, but with respect to grasses, both the herbicide mixtures were more or less similar in effectiveness. Penoxsulam + cyhalofop butyl @ 135 and 136 registered higher weed control efficiency and lower weed index than other treatments. Uncontrolled weed growth caused a yield reduction of 50.38 per cent. Herbicide treatments significantly reduced the nutrient uptake by weeds and enhanced the nutrient uptake by crop over weedy check. The higher doses of penoxsulam + cyhalofop butyl (125,130 and 135 g ha"') and bispyribac sodium + metamifop (70, 80 and 90 g ha*') were more effective in maintaining higher nutrient content in soil. Dynamics of soil microbial population, earthworm population, soil enzyme status and organic carbon content of soil consequent to the application of herbicide mixtures revealed that, both penoxsulam + cyhalofop butyl and bispyribac sodium + metamifop at their tested doses did not have any inhibitory effect. Results of screening trial revealed that maize was the most sensitive indicator plant for both the herbicide mixtures. Dry weight and fresh weight of maize shoot were adjudged as the best parameters for assessing the residual effect of bispyribac sodium + metamifop and penoxsulam + c>^Iofop butyl in soil respectively. Pot culture bioassay studies revealed that the tested herbicide mixtures and their doses did not have any residual effect. In vitro sensitivity studies of bispyribac sodium + metamifop and penoxsulam + cyhalofop butyl to Rhizoctonia solani pointed out that both the herbicide mixtures inhibit the growth of Rhizoctonia solani. Studies on the in vitro effect of herbicide mixtures to Trichoderma viride indicated that bispyribac sodium + metamifop was safe to the fungus, whereas penoxsulam + cyhalofop butyl was moderately toxic. Compatibility studies revealed that both the herbicide mixtures were highly compatible with Psetidomonas fluorescenSy Azospirillum lipoferum and Azotobacter chroococciim. Weed seed bank assay results indicated the effectiveness of the higher doses of penoxsulam + cylialofop butyl (135, 130 and 125 g ha'') in depleting the seed bank compared to other treatments. The present study revealed the superiority of heibicide mixtures over individual herbicides in the management of weeds in wet seeded rice. Application of penoxsulam + cyhalofop butyl @ 135 or 130 g ha*', at 15 DAS could be adjudged as the most economic and ecofriendly weed management practice for wet seeded rice as evidenced by high weed control efficiency, net returns and B: C ratio; environmental safety, high inhibitory effect to Rhizoctonia solani and good compatibility with bio control agents and bio fertilizer organisms.ThesisItem Open Access Fertigation and mulching in oriental pickling melon (Cucumis melo var. conomon (L.) Makino) under high density planting(Department of Agronomy,Vellanikkara, 2016) Ashly, P; KAU; Joseph, P AA field experiment was conducted to study the eficcts of 'Fertigation and mulching in oriental pickling melon {Cucumis melo vor.conomon (L.) Makino ) under high density planting and LDPF mulching in the summer rice fallow at the Agricultural Research Station (ARS) , Mannuthy from December 2014 to February 2015. High density planting of short duration less spreading high yielding variety of op melon at 33,333 plants per hectare was found to increase the yield of op melon more than double the yield at the recommended population of 10,000 plants per hectare. Under high density planting there is a proportionate increase in the demand of water and nutrients, which are crucial for the balanced growth, development and yield of the crop. The purpose of this experiment was to find out an optimum level of irrigation, fertilizer which will be supplied as drip fertigation for the highest yield and quality of fruits under polythene mulched condition. There were nine drip fertigation combinations with three levels of irrigation (75, 100 and 125 per cent Ep ) and 3 levels of fertilizers (200, 250 and 300 per cent of RDF), and one control which were laid out in Randomized Block Design with three replications. There was a significant increase in the characters like length of vine, number of leaves per vine, number of secondary branches per vine, leaf area index and shoot dry matter production at harvest with increase in irrigation levels from 75 per cent Ep to 125 percent Ep. At the same lime, other growth attributes such as number of primary branches per vine and days to fust male and female flower appearance didn't show any significant effect with various drip irrigation levels. Similarly, under high density planting and polythene mulching, the length of vine, number of leaves per vine, number of secondary branches per vine, LAI and shoot dry matter production at harvest increased linearly with increase in fertilizer levels from 200 per cent to 300 per cent of recommended dose. But increase in fertilizer level did not make any significant effect on the number of primary branches of OP melon. It remained constant around 2 in all levels of irrigation and fertilizer. The interaction between irrigation and fertilizer levels was not significant in any of the characters viz., length of vine, number of leaves per vine, number of primary and secondary branches per vine and LAI and shoot dry matter production at harvest. Per hectare yield of crc^ as well as various yield attributes like number of fruits per plant, average fruit weight, average volume of fruit and fruit yield per plant were not affected significantly by various irrigation levels. However, the average weight and volume of fruits increased slightly and non significantly with increase in irrigation levels from 75 per cent Ep to 125 per cent Ep. All other parameters like number of fruits per plant, yield of fruits per plant and fruit yield per ha recorded maximum value at 100 per cent Ep and the value declined gradually when irrigation level was increased to 125 percent Ep. Even though the weight and volume of individual fruits were maximum at 125 per cent Ep, the number of fruits per plant was less in this treatment, which ultimately resulted in a raluction in per ha yield of the crop. Number of fruits per plant, fruit yield per plajit and per hectare yield of fruit showed significant increase with increase in fertilizer level from 200 per cent to 250 per cent of recommended dose of fertilizer. But a further increase in fertilizer level affected the above characters negalively.So also, among the fertilizer levels, the average weight and volume of fruits were highest at 250 per cent RDF even though the effect was non- significant. The interaction between irrigation and fertilizer levels was not significant on the weight of fruits per plant and average weight and volume of fruits. But, there was significant elTect of interaction between irrigation and fertilizer levels on characters like ftuit yield per plant and per ha. Highest fruit yield per plant and highest per ha fruit yield were recorded at IiFi which was significantly superior to all the other combinations except I3F2,. So, there was positive interaction up to 100 per cent Ep and 250 per cent of recommended dose of fertilizer level when applied together as drip fertigation with LDPE mulching. Number of days taken for the appearance of flowers and the number of days taken for harvest did not show significant variation under various levels of drip fertigation. The interaction between irrigation and fertilizer levels was also non- significant on these characters. In general, days to first male flowering and female flowering were 21 and 26 respectively in drip fertigation treatments, while they were 25 and 29 respectively in control. Fruits were harvested 63 and 68 days after planting in drip fertigation treatments and control plots respectively. There was an increase in fruit dry weight with increase in irrigation levels from 75 per cent Ep to 100 per cent Ep and then it declined with further increase in irrigation level to 125 per cent Ep and the highest fruit dry matter production was recorded with 250 per cent of RDF compared to both 200 and 300 per cent of RDF. The interaction between irrigation and fertilizer levels also significantly influenced the fruit dry matter production. The maximum was observed at a combination of irrigation with 100 per cent EP and fertilizer with 250 per cent RDF. Both nitrogen and phosphorus content of leaves at 45 DAS increased significantly with increase in irrigation levels from 75 per cent to 125 per cent Ep under drip irrigation. But the increase in potassium content with increase in irrigation levels was non- significant. But the concentration of nitrogen, phosphorus and potassium in leaves of op melon increased significantly with increase in fertilizer levels from 200 per cent RDF to 300 per cent RDF. This shows the tendency of op melon to absorb and accumulate more and more NPK in their leaves with an increase in their availability in the root zone. The interaction between the tested irrigation and fertilizer levels did not show any significant effect on the content of primary nutrients in leaves of op melon at 45 DAS. Nitrogen content of shoot at harvest increased significantly with irrigation levels from 75 per cent Ep to 125 per cent Ep and fertilizer level from 200 per cent to 300 per cent of RDF. The fruit nitrogen level at harvest remained constant with slight variation, with the different levels of irrigation and fertilizers. At the same time, the interaction between any of the tested irrigation and fertilizer levels did not make any significant effect on shoot and fruit nitrogen content at harvest. Levels of irrigation significantly influenced the total N uptake by the crop at harvest. With increase in irrigation levels, N uptake increased significantly up to band then decreased, b and b were at par. The total nitrogen uptake by the crop at harvest increased with increase in fertilizer levels upto F2 and then decreased. F2 was significantly superior to F| and F3. The interaction between irrigation and fertilizer levels didn't make an\ significant effect on the character. Phosphorus content of shoot at harvest of op melon was found increasing significantly with increase in drip irrigation levels from 75 per cent Ep to 125 per cent Ep and fertilizer from Fi to F3 levels. At the same time, the fruit phosphorus content at harvest was not significantly affected by an increased application of phosphorus in soil.Fruit P content at harvest was not influenced by levels of irrigation and fertilizers. None of the combinations between irrigation and fertilizer levels showed significant superiority in increasing either shoot or fruit phosphorus content in OP melon. Levels of irrigation significantly influenced the P uptake by the crop. With increase in irrigation levels, P uptake increased up to b- But b and b were at par and significantly superior to b- With increase in fertilizer levels, the P uptake by the crop also increased up to F3. But F2 and F3 were at par and significantly superior to Fi. The Interaction between irrigation and fertilizer levels could not make any significant effect on P uptake by the crop. Irrigation and fertilizer levels significantly influenced the potassium content of shoot at harvest, but not the content of fruit. Significantly the highest potassium content in shoot was recorded at irrigation level of 125 per cent Ep and fertilizer level of 300 % RDFfFj). The fruit potassium content remained constant with different irrigation and fertilizer levels. Levels of irrigation significantly influenced the total K uptake by the crop. With increase in irrigation levels, K uptake increased significantly up to b (100 per cent Ep) and then decreased. Similarly, total K uptake also increased significantly upto 250 per cent RDF and then decreased. The interaction between irrigation ai^d fertilizer levels didn't show any significant influence on total K up lake. With increase in drip irrigation from 75 to 125 per cent Ep field water use efficiency decreased from 215.6 ( kg ha-mm ') to 145.8 ( kg ha-mm'') . Among the fertilizer levels, highest field water use efficiency was reported by 200 per cent RBF (181.9 kg ha-mm"') . However, the variation in FWUE among the fertilizer levels was not as significant as that observed in irrigation treatments. High level of irrigation in the control practice reduced FWUE in a significant way and was the lowest at 42.7 kg ha-mm"'. Soil chemical properties such as pH and Electrical Conductivity didn't show appreciable variation due to the various levels of irrigation and fertilizer. This indicates that chemical properties of soil are not likely to be influenced by short term management practices like irrigation and fertilizer application. In all the treatments and control, soil moisture content was the highest in the surface layer of 0-15 cm and the lowest in the bottom most layer of 30-45 cm. The decrease in soil moisture content from surface to the bottom most layer was gradual. In each layer, moisture content increased with increase in drip irrigation level from 75 % Ep to 125 % Ep. The moisture content in each layer was more in the control plot as it received more moisture through flood irrigation. In each layer the variation in moisture content was negligible within every level of drip irrigation due to the influence of varying levels of fertilizers. Keeping quality of the fruits was not affected by irrigation or fertilizer levels up to 45 days after harvest under high density planting with LDPE mulching. All the drip fertigation treatments were far superior to control on increasing the net profit per hectare and also the net income per rupee invested. In all the irrigation treatments F2 fertilizer level increased the net profit per hectare as well as net income per rupee invested in a significant way as the increase in fertilizer level above Ft had negative effect on crop yield. Among the treatment combinations I2F2 recorded the highest net return of Rs. 531581 per hectare followed by I3F2 of Rs 513651. Among the treatment combinations also I2F2 recorded the highest net income of Rs 2.06 per rupee invested followed by 1.95 by both I3F2 and I}F2. The study may be concluded by stating that for the most profitable production of op melon in the summer rice fallows of Kerala, high yielding less spreading varieties like Saunhagya should be planted at a high density of 33,333 plants per hectare and managed by drip fertigation at 1 GO per cent Ep and 250 per cent RDF with LDPE mulching. This has produced the highest net profit per hectare and net income per rupee invested.ThesisItem Open Access Characterization and management of weedy rice (Oryza sativa f spontanea)(Department of Agronomy, College of Agriculture, vellayani, 2016) Anjali, K; KAU; Ameena, MThe study entitled ‘Characterization and management of weedy rice (Oryza sativa f spontanea)’ was carried out as four separate experiments conducted at COA, Vellayani and farmers’ fields of Nemom block during 2014-16. The main objectives of the study were morpho-physiological and agronomic characterization of weedy rice morphotypes of Kerala; formulation of a management strategy and assessment of crop weed interference under elevated carbon dioxide concentration. Experiment I. ‘Morpho-physiological and agronomic characterization of weedy rice morphotypes’ was conducted as pot culture laid out in completely randomized design with eight weedy rice morphotypes collected from major rice tracts of Kerala (Trivandrum, Kuttanad, Kole lands, Palakkad, Kozhikode and Ezhome). Morphological characterization of weedy rice morphotypes using morphometric descriptors and its comparison with cultivated varieties revealed that during initial stages most of the weedy rice morphotype possess similar morphological characteristics as the cultivated varieties. Physiological characterization of weedy rice morphotypes revealed no significant variation in chlorophyll content, total soluble protein and stomatal characteristics with cultivated rice varieties. However, root growth in terms of volume and dry weight was significantly higher for most of the morphotypes collected from Trivandrum, Kuttanad, Palakkad, and Ezhome. Earliness in 50% flowering was observed in all the weedy rice morphotypes compared to cultivated rice. Sterility of weedy rice morphotypes were significantly higher (17.77 to 32.79%) compared to cultivated rice varieties (9.23 to 12.85%). All the weedy rice morphotypes collected showed a prominence in awn length ranging from 2.37 to 9.23 cm. An average grain and straw yield of 4.89 and 16.14 g plant-1 and 1000 grain weight of 20.42 g was recorded by weedy rice morphotypes. Shattering percentage expressed as grain threshebility was significantly high for weedy rice morphotypes ranging from 29.73 to 46.32%. The seeds of weedy rice recorded wide variation in longevity ranging from 4.96 to 15 months which is an indication of variable seed dormancy. Experiment II. ‘Management of weedy rice by enhancing rice competitiveness’ was undertaken as micro plot study by raising cultivated rice and most common weedy rice morphotype and maintaining a standard weedy rice population of 7 plants m-2. To enhance rice competitiveness, three levels of seed rates viz., 100,120 and 140 kg ha-1 in combination with three types of priming techniques, i.e., without priming, hydropriming and hardening (2.5 % KCl) were included.Among the treatments, seed rate of 100 kg ha-1 along with hydropriming(T2) recorded significantly higher number of grains per panicle (120.02), grain yield (4.44 t ha-1) and straw yield (6.71 t ha-1) which was on par with T5 (120 kg ha-1 + hydropriming). Confirmatory trial at farmers’ field revealed that seed rates of 100 kg ha-1 or 120 kg ha-1 along with hydropriming (T2& T5) resulted in superior yield attributes inrice viz., number of grains per panicle, grain and straw yield ha-1.Weedy rice count m-2 and dry weight were significantly lower under these treatments. T2 (100 kg+ hydropriming) along with T5 (120 kg+ hydropriming) turned out to be the most economic treatment with a B:C ratio of 1.68 and 1.64 respectively. Experiment III. ‘Effect of elevated CO2 concentration on growth of rice and weedy rice’, was undertaken as pot study under elevated CO2 concentration of 500 ppm in Open Top Chamber (Chamber A) and in ambient conditions (Chamber B and open field). The most common morphotype of weedy rice and two cultivated rice varieties (Jyothi and Uma) were selected for the study. Significant variations in vegetative (no of tillers, leaf area index and leaf area duration) as well as yield attributes and yield (no. of grain panicle-1, grain yield plant-1) were observed under elevated CO2 levels in all these three systems. Higher grain yield per plant was recorded by weedy rice in Chamber A with an elevated CO2 level (1.73 times higher than open condition), followed by Chamber B (recorded 1.19 times more than open condition). However, the extent of response varied among the cultivars under varying atmospheric situations with Uma showing a greater percentage increase in grain yield (51.4% in Chamber A and 40% in Chamber B) followed by weedy rice (42.3% in Chamber A and 16% in Chamber B). The study revealed significant variation among the weedy rice morphotypes. Cultivated rice and weedy rice exhibited morphological similarity during initial stages of growth. Seed rate of 100 kg ha-1 with hydropriming can be recommended as the most effective and economic management strategy for weedy rice. The response of weedy rice to elevated CO2 was more compared to cultivated rice varieties.
