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  • ThesisItemOpen Access
    Spatial mapping of flood prone areas and risk assessment of Chalakudy river basin using HEC-HMS and HEC-RAS models
    (Department of Irrigation and Drainage Engineering, Kelappaji college of Agricultural Engineering and Technology,Tavanur, 2021-10-17) Gudidha Gopi.; Rema, K P.
    Floods are one among the most devastating natural disasters that affects life on the globe. For the planning and design of water resources projects in the preferred area, planners and engineers usually require reliable estimates of flood magnitude and frequency. Kerala state in the Indian sub continent received a catastrophic flood in the year 2018. The present study attempts to model the flood flows and map the flood prone areas of a river basin in Kerala. The Chalakudy river basin, one of the worst-affected river basins due to heavy rains and floods was selected for the present study. This is the fifth largest river in Kerala. The basin is predominant with agricultural land and falls under the humid tropical zone, where water resources planning and management is necessary for irrigation scheduling, flood control and design of various engineering structures. In order to address the above issues, an attempt was made to calibrate and validate HEC-HMS model for simulating the flood hydrograph for the Chalakudy river basin. Flood frequency analysis was carried out to estimate the flood peak values using frequency distributions in HEC-SSP software. The results were compared with the estimated flood peak values for different return periods obtained from the HEC-HMS model. Hydraulic routing was done in HEC-RAS model and the flood inundation maps were prepared. The cadastral level risk areas were identified based on water surface profiles of velocity and depth of flood extent and its characteristics. Food vulnerability maps based on land use patterns were developed in order to identify the severely affected land uses. The HEC-HMS model for the basin was developed using SCS-UH, SCSCN, Recession and Muskingum methods to find out the loss rate, runoff transformation and routing of flood respectively. Statistical performance indices of the model, Nash-Sutcliffe efficiency (NSE) and Coefficient of correlation (R²) values were obtained above 0.7, Error in Peak Flow (%) and Error in Volume (%) were figured below 20% and Root Mean Square Error-Standard Deviation Ratio (RSR) was acquired as 0.5 and below. These values indicated that HEC-HMS model simulation performed well in both calibration and validation. The frequency discharge values calculated using Log Pearson type-III distribution indicated a high degree of similarity to the HEC-HMS generated values with an R 2 value of 0.862. The results of the Log Normal and Gumbel distributions are significantly lower than those of the HEC-HMS model values. The assessment of the vulnerability due to the flooding was made with regard to the land use pattern and cadastral level risk map of Chalakudy river basin was developed for different return periods. Kadukutty Panchayat located in the downstream of Chalakudy river basin was found to be the maximum flood inundated area for 10 year return period ( 557 ha) and for 200 year return period (681 ha). Manjapra Panchayat located in upstream was found to be the least flood inundated area for 10 year return period (6 ha) and for 200 year return period (9 ha). Annamanada, Kadukutty, Melur and Pariyaram panchayats were under high risk areas, with depths greater than 20 m. Ayyampuzha, Chalakudy, Mala, Kuzhur, Parakkadavu and Puthenvelikara panchayats were under medium risk areas with depths varying from 10 to 20 m. Athirappilly, Manjapra and Karukutty panchayats were under low risk areas with depths less than 10 m. The flood vulnerability maps were generated by intersecting the flood plain land use map with the flooded area polygons. Paddy land near to the river banks was found to be the highest inundated by different return period floods, followed by forest and other vegetation, barren land and other land use classes
  • ThesisItemOpen Access
    Breeding yard long bean(Vigna unguiculata subsp.sesquipedalis (L.) Verdcourt) for anthracnose resistance through conventional and molecular marker analysis
    (Department of Vegetable Science College of Agriculture ,Vellayani, 2022) Merin Elza George; Sarada,S
    The study entitled ―Breeding yard long bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt) for anthracnose resistance through conventional and molecular marker analysis‖ was carried out at the Department of Vegetable Science, College of Agriculture, Vellayani, Thiruvananthapuram, Kerala, during 2019-2022. The objective of the study was to identify molecular marker(s) linked with anthracnose disease resistance in the F2 segregating population of yard long bean, using bulk segregant analysis to enable marker assisted selection along with conventional breeding. The study was undertaken in six experiments. In experiment I, 50 genotypes of vegetable cowpea collected from different parts of India, including the released varieties of SAUs and ICAR institutes were screened against the most virulent isolate of Colletotricum gloeosporioides through artificial inoculation. Among the 50 genotypes tested, VU 53, with semi-trailing growth habit was found to be highly resistant with disease severity of 3.67 ± 0.13 %. Three susceptible, high yielding long podded varieties viz., KAU Deepika, Vellayani Jyothika and Githika, selected as female parents were crossed with VU 53, the most resistant genotype as male parent for the development of three hybrids. In experiment II, two crossing blocks were laid to produce the seeds of three hybrids and their F2 progenies. The three hybrids were evaluated along with the parents under replicated trial in the main field for trailing nature, yield and quality in experiment III. Significant variation was noticed on mean performance of yard long bean parents and hybrids for most of the characters studied. Earliest flowering was observed in KAU Deepika x VU 53 (57.33 ± 0.57 days) and delayed flowering in Githika x VU 53 (71.66 ± 1.15 days). Among the hybrids, the highest pod length was recorded in KAU Deepika x VU 53 (24.50 ± 1.00 cm), while the Vellayani Jyothika x VU 53 had the maximum pod girth (2.90 ± 0.10 cm). Maximum pod weight and pods per plant was recorded in KAU Deepika x VU 53 (19.22 ± 0.58 g and 79.33 ± 0.59 respectively) among hybrids. The cross Vellayani Jyothika x VU 53 (16.55 ± 0.20 g) exhibited maximum seed weight. Among the three hybrids, KAU Deepika x VU 53 (1416.00 ± 126.09 g) recorded the highest yield per plant and was on par with Githika x VU 53 (1343.33 ± 75.06 g). Among the hybrids, KAU Deepika x VU 53 (67.85 ± 0.96 days) was significantly superior for days to harvest. The longest duration among hybrids was observed in KAU Deepika x VU 53 (126.56 ± 0.37 days) and the shortest duration was recorded in Vellayani Jyothika x VU 53 (121.31 ± 0.58 days). High heritability and genetic advance was recorded for vine length, days to first flowering, pod length, pod weight, pods per plant, yield per plant, yield per plot, hundred seed weight and keeping quality. Yield per plant had significant positive phenotypic and genotypic correlation with pod weight, followed by pods per plant, length of terminal leaf, seeds per pod, pod length, crop duration, keeping quality and days to harvest. Pods per plant could be considered as the most important yield trait for enhancing the yield in yard long bean because of its high, positive correlation and direct effect with yield per plant along with high heritability and genetic advance. In experiment IV, parents, three hybrids and F2 progenies were evaluated for resistance to natural incidence of C. gloeosporioides in the main field, as unreplicated trial and without any plant protection measures. All the three F1 were found to be field tolerant. Out of 175 F2 plants of the cross KAU Deepika x VU 53, 164 plants were susceptible and 11 were resistant. In the case of Vellayani Jyothika x VU 53, 175 plants were susceptible among the 187 individual F2 progenies observed. Similarly, in the cross Githika x VU 53, 188 plants were susceptible while 12 plants were found to be symptomless. The F2 progenies of the high yielding hybrid KAU Deepika x VU 53 were evaluated for resistance to C. gloeosporioides through artificial inoculation in experiment V. Out of 196 plants, 185 plants were found to be susceptible whereas 11 plants were resistant which could be utilized in marker assisted breeding programme. The segregation for anthracnose resistance in F2 plants was in the ratio 15:1 (185 susceptible plants out of 196), which suggests that the inheritance of anthracnose resistance may be controlled by two recessive genes. Bulked segregant analysis was done using the DNA from the resistant parent, susceptible parent, resistant F2 bulk and susceptible F2 bulk in experiment VI. Bulked segregant analysis with the SSR primer CLM0008 revealed a polymorphic band at ≈ 300 bp which was appeared in the resistant parent and bulk. Bulked segregant analysis with ISSR primer UBC 811 produced polymorphic bands at ≈ 1100 bp, which were present in resistant parent and resistant bulks. The identified markers linked with resistance were validated over the resistant F2 lines obtained.
  • ThesisItemOpen Access
    Response of banana Musa (AAB) 'Nendran' to nutrient sources
    (Department of Fruit Science, College of Agriculture ,Vellanikkara, 2021) Manohar Lal Meghwal.; Jyothi, M L; KAU
    anana is the leading tropical fruit in the world market today with a highly organized and developed industry. Banana having a root system spread in the top 60 cm soil, is heavy feeder of nutrients and requires large quantities of nutrients for its growth, development and yield. Nutrient removal from soil by crops must be replenished. Under good management conditions and adequate supply of biofertilizers and organic manures, the nutrient removal can be replenished and soil physical, chemical and biological properties can be improved. Organic and inorganic sources of nutrients have significant influence on fruit quality and soil characteristics. The current agricultural policy emphasize a shift towards safe agricultural practices for which organic management is the best option. However the crop behaviour under organic and inorganic management needs elaborate studies. Hence the research entitled ‘Response of banana Musa (AAB) 'Nendran' to nutrient sources was formulated to elucidate response of banana in terms of growth, yield and quality to nutrient sources and to compare the fruit quality of banana grown under organic and conventional systems in farmer’s field. The study revealed that vegetative growth of Musa Nendran banana was not influenced by different sources of nutrients in early stage in both the years but later differences were recorded between the treatments. Plant height, number of leaves and pseudostem girth showed significant differences from 90 DAP. At bunching stage plant height and pseudostem girth were higher in organic treatments. There was significant difference in pseudostem girth between the treatments throughout the growth stage of Nendran banana. Among the treatments, T8 resulted in better growth of plants. Leaf characters like number of leaves and leaf area index were not influenced significantly between organic and integrated nutrient management. Early leaf production was also noticed in treatment T8 as indicated by the observations on phyllocron. Growth was delayed in control where no manures and fertilizers. In general more number of leaves per plant and lesser duration for leaf emergence was recorded in both the years in organic treatments. Chlorophyll production in the index leaf of banana was influenced with organic and inorganic nutrition. Chlorophyll a, b and total chlorophyll in the index leaf were distinctly higher in treatment T8 (fertigation with FYM) which was on par with treatments T3 and T5 where organic manures alone were applied. Early flowering and early harvesting were observed in organic treatments. Higher total biomass production was recorded in organic treatments. Yield and yield attributing characters like bunch weight, number of finger, finger weight were highest in treatments with organic sources of nutrients. The mean bunch weight was influenced significantly by organic and inorganic sources of nutrients. Fertigation with organic sources of nutrients resulted in the production of heavier bunches in both years. Maximum bunch weight was recorded from treatment T8 which was on par with other organic treatments as well as integrated management with fertilisers applied as fertigation as well as based on soil test results. No significant variation was observed between treatments on number of hands per bunch and finger characters like finger length and girth. Peel thickness of fruits were not significantly influenced but the pulp to peel ratio was significantly influenced by the treatments. Pulp to peel ratio was higher in all treatments other than T1 and control where T1 is the POP recommendation for TC banana under integrated nutrient management. Yield per plant was positively correlated with available N, P, K, Calcium, magnesium, sulphur, Zn, Cu, B, content of the soil. Yield was also positively correlated with soil properties like pH, organic carbon content, CEC, Bulk density, and Dehydrogenase enzyme activity. Higher biomass production was recorded in plants that received nutrients from organic sources compared to integrated nutrient management and control. Shelf life of fruits were improved in organic treatments. Fruit quality parameters like TSS, Total sugars, ascorbic acid and β carotene of ripe banana fruits were improved in organic treatments compare to inorganic system. Sensory score of ripe fruits and fruit chips were maximum in organic treatments. The taste of ripe banana fruits was improved in plants grown under organic treatments. Fertigation with organic manures (T8) resulted in improved fruit quality of Nendran banana in both the years. Different soil physical and chemical properties also improved when nutrients were supplied through organic sources. Soil pH, electrical conductivity, organic carbon content, cation exchange capacity, available, N, P, K, Mg, Iron, Copper, Zinc, Mn and boron were better in soils receiving organic manures alone. Similarly the soil biological properties like dehydrogenase activity, nitrogenase activity, microbial biomass carbon, and viable counts of total fungi, bacteria and actinomycetes were better in organic treatments. Bulk density of soil was low in soils receiving organic manures alone compared to integrated nutrients. Total uptake of nutrients in organic and integrated nutrient management system was compared. Uptake of N, Ca, S, Fe, Mn, Zn and Cu was higher in organic system of cultivation of banana compared to integrated system. Higher benefit cost ratio was recorded banana grown in organic system. The study revealed that organic sources of nutrients improved soil properties and thereby improved growth, yield and quality of banana.
  • ThesisItemOpen Access
    Integrated nutrient management in minisett cultivation of elephant foot yam {Amorphophallus paeoniifolius (Dennst.) Nicolson}
    (Department of Agronomy, College of Agriculture, 2022) Dhanalakshmi V N.; Rajasree G
    The study entitled “Integrated nutrient management in minisett cultivation of elephant foot yam [Amorphophallus paeoniifolius (Dennst.) Nicolson]” was conducted at the Instructional Farm, College of Agriculture, Vellayani, Thiruvananthapuram to standardise the minisett size in elephant foot yam and to investigate the effect of integrated nutrient management practices on growth, yield, quality and economics of cultivation and to study the rooting and tuberisation pattern of minisett planted elephant foot yam. The investigation consisted of two experiments; standardisation of minisett corm size and integrated nutrient management practices (field experiment) and rooting and tuberisation pattern study (pot culture) and was undertaken during April to November 2018 and 2019. The first experiment was laid out in RBD with 15 treatment combinations and a control, replicated thrice. The treatments comprised three minisett corm sizes (s1-200 g, s2-300 g and s3-400 g) and five integrated nutrient management practices (i1-100 per cent NPK, i2-75 per cent NPK with 50 per cent N substitution through coir pith compost, i3-75 per cent NPK with 50 per cent N substitution through coir pith compost + PGPR mix-I + AMF, i4-50 per cent NPK with 50 per cent N substitution through coir pith compost, i5-50 per cent NPK with 50 per cent N substitution through coir pith compost + PGPR mix-I + AMF). The minisett corms and control corms (1 kg) of elephant foot yam var. Gajendra were planted at a spacing of 60 x 60 cm and 90 x 90 cm respectively. The recommended dose of N, P and K (100:50:150 kg NPK ha-1 ) for elephant foot yam was modified based on soil test data. Substitution of N with coir pith compost was carried out on N equivalent basis, and P and K were given through chemical sources. The pot culture experiment was laid out in CRD with 14 plants per treatment with the same treatments as the field experiment. The number of days taken for 100 per cent sprouting of seed corms varied between minisett corms and control corms and the latter sprouted early. The minisett corm s3 (400 g) recorded taller plants, higher leaf area index, pseudostem 281 girth and canopy spread. Application of 100 per cent NPK (i1) as chemical fertilizer produced taller plants and higher canopy spread during later stages compared to INM practices. Among the INM treatments, i3 (75 % NPK with 50 % N substitution through coir pith compost + PGPR mix-I + AMF) found superior with respect to growth attributes such as plant height and canopy spread. The treatment combination s3i1 (400 g + 100 % NPK as chemical fertilizer) produced taller plants and recorded higher canopy spread. Among the interactions including INM practices, taller plants were produced by s3i3 and s3i5 and higher canopy spread was recorded with s3i2, s3i3 and s3i5. Control plants (1 kg) showed taller plants, higher pseudostem girth and canopy spread at all stages of observation. The s3 recorded higher yield attributes, corm yield (48.81 and 50.57 t ha-1 during first year and second year, respectively) and pooled corm yield (49.69 t ha1 ). The treatments, i1 (100 % NPK) recorded significantly the highest yield attributes and yield. Among the different INM practices, i3 recorded higher yield attributes and corm yield (38.26 and 45.37 t ha-1 during first year and second year, respectively), while corm yield in pooled mean analysis (41.82 t ha-1 ) was also higher in this treatment. The s3i1 (400 g + 100 % NPK as chemical fertilizer) produced significantly the highest yield attributes and yield among all the treatments. Among the INM combinations, s3i3 recorded higher yield attributes, corm yield and higher pooled mean of corm yield (51.29 t ha-1 ). Control recorded higher yield attributes than minisetts. Pooled analysis of corm yield ha-1 indicated that s3i1, s3i2, s3i3 and s3i5 were superior to control and s2i1, s2i2, s2i3 and s3i4 were on par with control. Quality attributes like starch, total sugar, crude protein and crude fibre content of corm were non significant with respect to the treatments. Higher dry matter content was obtained in i4 (50 % NPK with 50 % N substitution through coir pith compost). The lower content of oxalic acid was recorded with i5 and i4 and the higher content was in i1 (100 % NPK). The minisett corm s3 recorded superior results for nutrient content, uptake and nutrient harvest indices. The INM treatment, i3 recorded higher nutrient content and uptake, however the highest was recorded in i1 among all the treatments. The treatment s3i1 (400 g + 100 % NPK 282 through chemical fertilisers) recorded significantly the highest K uptake. Among the combinations including INM practices, s3i3 recorded higher K uptake during second year. The combinations, s3i1, s3i2, s3i3, s3i4 and s3i5 were found superior to control in case of nutrient uptake. Soil chemical properties after the field experiments were not significantly affected by the treatments. The treatment s3i1 (400 g + 100 % NPK) recorded the highest net income and BCR during both the years. The highest net income and BCR were recorded from s3i2 during first year and s3i3 during second year, and the two year mean of net income and BCR were also highest in the case of INM treatment s3i3. In pot culture study, chemical properties of potting medium at monthly intervals up to harvest were not significantly affected by the treatments except for organic carbon content. The treatment i3 (75 % NPK with 50 % N substitution through coir pith compost + PGPR mix-I + AMF) recorded higher organic carbon content at 5 MAP. The minisett corm s3 excelled in rooting pattern and root anatomical parameters. Higher number of roots per plant was recorded in i2 and i3, however, these treatments were on par with i1 (100 % NPK). Higher weight of roots per plant was observed in i5, i4 and i3 and, root anatomical parameters were superior in i3. The interactions, s3i5, s3i4 and s3i3 recorded the highest weight of roots per plant. Higher root parameters were recorded in control than in minisetts and, in case of number of roots per plant s3i1, s3i2 and s3i3 at 4, 6 MAP and harvest, and s3i1 at 5 MAP recorded on par results with control. In the case of weight of roots per plant, s3i3 was on par with control at harvest. The roots of plants applied with AMF showed mycelial network from 3 MAP up to the harvest, and in the maximum growing stage of 5 MAP, vesicles were found in between the cells of the roots of AMF applied plants. Higher root colonization was observed in s3i3 at 5 MAP. Corm initiation was observed between 1 MAP and 2 MAP in control and between 2 MAP and 3 MAP in all other treatments. The s2 (300 g) during 3-4 MAP and s3 (400 g) during all other stages had significantly the highest corm bulking rate (CBR). Higher corm bulking efficiency (CBE) was recorded in s2 during 3-4 MAP, s1 during 4-5 MAP and 6 MAP-harvest and s3 during 5-6 MAP. 283 The INM treatment i3 showed superior results for CBR and CBE, however, higher CBR and CBE were recorded in i1 (100 % NPK) among all the treatments. The s3i1 (400 g + 100 % NPK)showed the highest CBR and CBE during 4-5 MAP and 5-6 MAP among all the treatments. Among the INM interactions, s3i3 during 3-4 MAP and 5-6 MAP; s3i2 during 4-5 MAP and s3i4 during 6 MAP-harvest recorded higher CBR. The s2i3 during 3-4 MAP, s1i3 during 4-5 MAP, s3i3 during 5-6 MAP and s1i5 during 6 MAP-harvest recorded higher CBE. Higher corm weight per plant was recorded with s3. The i1 recorded the higher corm weight per plant among all the treatments, and at 5 MAP, i1 was on par with i3. Among the INM treatments i2 at 3 MAP and i3 at all other stages recorded higher corm weight per plant. Among interactions, s3i3 produced higher corm weight, however, among all the treatments the highest corm weight was noted in s3i1 at all stages except at 4 MAP. Control produced significantly higher corm weight per plant than minisetts. Uptake of nitrogen at 3 MAP and uptake of phosphorus at harvest were higher in s3. The INM treatment i3 recorded higher microbial population and dehydrogenase activity in the potting medium and among the interactions, higher dehydrogenase activity was recorded with s3i3. Significant and positive correlations were observed between corm weight per plant vs. root anatomical parameters and nutrient uptake vs. root anatomical parameters. It is evident from the present study that planting of 400 g minisett corm resulted in better growth, yield and quality of elephant foot yam. Application of 75 per cent NPK with 50 per cent N substitution through coir pith compost + PGPR mix-I [@ 10 g per pit (dry cow dung: PGPR mix-I in 50:1 proportion) - at planting and 2 MAP] + AMF (@ 10 g per pit - at the time of planting) in elephant foot yam resulted in superior growth, yield and quality under INM system. Planting of 400 g minisett and application of 75 per cent NPK with 50 per cent N substitution through coir pith compost + PGPR mix-I + AMF under an INM system could be recommended for economic production of minisett elephant foot yam. Rooting and tuberisation of elephant foot yam were found superior in planting of 400 g minisett corm with application of 75 per cent NPK with 50 per cent N substitution through coir pith compost + PGPR mix-I + AMF.
  • ThesisItemEmbargo
    Genetic diversity analysis for nutrient efficiency and identification of nutrient responsive genes in cassava (Manihot esculenta Crantz)
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2023-02-10) Swathy Sivan; KAU; Arya, K
    The present study entitled “Genetic diversity analysis for nutrient efficiency and identification of nutrient responsive genes in cassava (Manihot esculenta Crantz)” was carried out in the Department of Plant breeding and Genetics, College of Agriculture, Vellayani and Division of Crop Improvement, ICAR-CTCRI, Sreekariyam, during 2019-2022. The study was undertaken to screen and characterize N and K-efficient genotypes in cassava and identify the traits contributing to nutrient efficiency and study their gene expression. Thirty genotypes of cassava comprising of landraces, released varieties and pre-release accessions from ICAR-CTCRI and KAU were taken for the study. Field evaluation was done to identify low input nutrient efficient lines where analysis of variance revealed significant difference among the genotypes for all the characters studied except the girth of tuber. High GCV, PCV, heritability and genetic advance were observed for traits like tuber yield, N and K efficiency, plant height, number of leaves, number of branches, stem N and K content. Tuber yield was positively correlated to N and K efficiency, plant height, leaf and stem weight, stem girth, mean weight of tubers, number of nodes, girth and length of tubers, while negatively correlated to tuber starch and dry matter content. Path analysis showed that tuber length gave highest positive direct effect on yield followed by number of tubers, number of leaves, tuber starch content, plant height and nitrogen efficiency. Diversity studies grouped the genotypes into eleven clusters and the characters that gave the maximum contribution to divergence were tuber dry matter content, N and K efficiency. Root studies on thirty genotypes revealed that root traits like number of nodal roots, basal roots, adventitious roots, storage roots and root length displayed significant positive correlations with N and K efficiency. Evaluation of five highly nutrient efficient genotypes at the three levels of fertilizers (0%, 25% and 50% of the recommended dose of fertilizers) showed overall significance for traits like plant height, the number of leaves retained, stem weight per plant, girth of the stem, tuber yield, length of tuber, stem K content, tuber K content, total N and K uptake, N and K efficiency. The highest yielder was KBH 18 followed by 8S501-2. Maximum N efficiency was observed for KBH18 followed by 15S409, while maximum K efficiency was recorded for 8S501-2 followed by 15S409. Results showed that from 0 to 25 % there is an escalation in tuber yield as well as N and K efficiency, while the values at 25 and 50% are on par. All the selected four genotypes showed significant superiority over the K efficient check variety – Sree Pavithra – in terms of tuber yield, N efficiency and K efficiency. The study identified nine nutrient responsive genes in cassava which includes NRT1, NRT3, NLP1, GPT2, AMT1, TAR2 for nitrogen and KUP3, KUP4, KUP8 for potassium. Expression studies done using these genes in contrasting genotypes for N and K efficiency raised under field conditions showed significant upregulations and downregulations in their expression for efficient and less efficient genotypes. Allele mining for allelic variations in contrasting genotypes (15S409 and Export kappa) for two genes (AMT2 and NTR3) didn’t show much significant variation. Although SNP differences were observed for NRT3 gene, further functional studies are required to confirm this result. The study identified three main nutrient efficient genotypes viz., KBH18, which was the highest yielder, highest in N efficiency and third highest in K efficiency, 8S501-2, which was second highest in yield, highest in K efficiency, third highest in N efficiency and also exhibited early bulking and 15S409, which was the third highest yielder, second highest in N efficiency & K efficiency. The superior genotypes identified in the present study can be subjected to field trials for confirming their superiority and release as a variety.
  • ThesisItemOpen Access
    Productivity enhancement of blackgram (Vigna mungo (L.) Hepper) intercropped in coconut gardens
    (Department of Agronomy, College of Agriculture,Vellayani, 2021) Pooja, A P; Ameena, M
    The research work entitled ‘Productivity enhancement of blackgram (Vigna mungo (L.) Hepper) intercropped in coconut gardens’ was undertaken at College of Agriculture, Vellayani during 2018-2021. The study aimed to identify shade tolerant blackgram varieties suitable for coconut gardens, to study the effect of foliar nutrition and plant growth regulators on growth and yield of the shade tolerant blackgram varieties intercropped in coconut garden and to work out the economics of cultivation. The investigation was carried out as two experiments: (i) screening of blackgram varieties for shade tolerance, and (ii) performance evaluation of shade tolerant varieties under foliar application of nutrients and growth regulators in rainfed coconut garden. The first experiment was conducted during Rabi 2019-20 in coconut garden having a light intensity equivalent to 50 per cent of that under open condition (56.25 klux), planted at a spacing of 7.6 m x 7.6 m. Seeds of 12 promising blackgram varieties collected from different research stations of south India (Sumanjana, DU 1, DBGV 5, VBN 5, VBN 6, VBN 8, Rashmi, CO 6, TAU 1, TAU 2, Blackgold and AKU 15) and three cultures (Culture 4.5.8, Culture 4.5.18 and Culture 4.6.1), were raised in micro plots laid out in randomized block design with three replications. The crop was raised as per KAU package of practices. The results of the study revealed significant variation in growth characters among the varieties screened for shade tolerance under partial shade in coconut garden. Plants of DBGV 5 were significantly taller (96.89 cm) with higher initial number of leaves at all the stages and was on par with Sumanjana and CO 6. Higher leaf area index (LAI) and leaf area duration were recorded in CO 6 (5.77, 65.66 days) and DBGV 5 (5.36, 58.40 days) followed by Sumanjana. Early flowering was observed in Sumanjana (34.33 days) and DBGV 5 (36.33 days). The variety DBGV 5 had the highest photosynthetic rate and resulted in significantly more pods per plant (23.67) which was on par with CO 6, VBN 5, VBN 6, Sumanjana and Rashmi. DBGV 5 produced the highest seed yield per plant (5.44 g) followed by VBN 5 and Sumanjana. Haulm yield per plant was higher for DBGV 5 (19 g) and was on par with VBN 5, Sumanjana and CO 6. The variety DBGV 5 produced the highest seed yield (1183 kg ha-1 ) followed by VBN 5, Sumanjana and CO 6. A higher harvest index of 0.24 was recorded by Sumanjana which was on par with DBGV 5 and VBN 6. Among the varieties screened, five varieties which performed better in terms of yield per unit area under the partial shade in coconut garden viz., DBGV 5, VBN 5, Sumanjana, CO 6 and VBN 6 were selected for experiment II undertaken in summer 2020 followed by the confirmatory trial during Rabi 2020 -21. The experiment was laid out in split plot design with five varieties (v1 - Sumanjana, v2 - DBGV 5,v3 - VBN 5,v4 - VBN 6,v5 - CO 6) as main plot treatments and six foliar sprays of nutrients and plant growth regulators as subplot treatments (f1: 19:19:19 (1%) at 45 and 60 DAS, f2: SOP (0.5%) at 45 and 60 DAS, f3: NAA 40 mg L-1 and salicylic acid 100 mg L-1 at pre-flowering (30-45 DAS) and 15 days later, f4: f3 + f1, f5: f3 + f2 and f6: Control - KAU POP). Among the varieties, Sumanjana (v1) grew taller during both the seasons and was comparable with CO 6 and DBGV 5 at harvest. Sumanjana produced higher number of branches with more number of leaves during both the seasons. At flowering, higher LAI, number and dry weight of nodules per plant were realized by Sumanjana and was on par with CO 6 (v5) in summer and DBGV 5 (v2) in Rabi. Sumanjana exhibited the highest crop growth rate (CGR) and relative growth rate (RGR) during both the seasons at 45-60 DAS. However, DBGV 5 recorded the highest net assimilation rate (NAR) between 30-45 DAS and 45-60 DAS during both the seasons. The highest chlorophyll content was recorded by DBGV 5 (1.96 mg g-1 fresh tissue) during summer and by Sumanjana (2.36 mg g-1 fresh tissue) during Rabi. The highest stomatal conductance (30.22 m moles m-2 s -1 and 28.34 m moles m-2 s -1 ) and lower stomatal index (15.16% and 13.34%) were recorded in Sumanjana during both the seasons. The variety Sumanjana flowered earlier compared to other varieties during both the seasons and produced the highest number of pods per plant (27.30 and 26.54). Hundred seed weight was significantly higher for DBGV 5 (5.01 g and 4.92 g) and remained at par with Sumanjana (4.99 g and 4.88 g) during both the seasons. Seed yield, haulm yield and total dry matter production (TDMP) were higher for Sumanjana and comparable with DBGV 5 during both the seasons. Sumanjana recorded higher NPK uptake during both the seasons followed by DBGV 5. The subplot factor foliar spray had significant effect on growth, physiological and yield attributes of blackgram varieties. Foliar spray of 19:19:19 (1%) at 45 and 60 DAS + foliar spray of NAA 40 mg L-1 and SA 100 mg L-1 at pre-flowering and 15 days later (f4) resulted in significantly taller plants, more number of branches and leaves. The highest CGR, RGR (at 45-60 DAS), LAI, number and dry weight of nodules per plant at flowering were recorded in f4 during both the seasons. During summer, f3, f4 and f5 recorded higher NAR between 45-60 DAS. Higher chlorophyll content and stomatal conductance were recorded by f4 during both the seasons. Plants supplied with f3 attained 50 per cent flowering earlier and was on par with f5 during both the seasons. Highest number of pods per plant, 100 seed weight, seed yield, haulm yield and TDMP were recorded by f4 during both seasons. The grain protein content was improved by f4 and was on par with f3, f1 and f5. The NPK uptake was higher in f4 and was on par with f3 and f5 during summer. Significantly higher organic carbon, available N and P was recorded in f4. Among the treatment combinations, Sumanjana (v1) with f4 produced taller plants at two months after sowing (MAS), higher number of branches and leaves per plant during summer and Rabi. Leaf area index, number of nodules and dry weight of nodules at flowering were higher for v1f4 followed by v2f4. Sumanjana in combination with f4 measured significantly higher CGR and RGR (at active growth stages), highest chlorophyll content, stomatal conductance and lower stomatal index during both the seasons. The variety Sumanjana with f4 produced superior number of pods per plant (30.24 and 29.40) and hundred seed weight during summer and Rabi. A higher seed yield was realized in v1f4 (1750 kg ha-1 ) which was on par with v2f4 (1713 kg ha-1 ) during summer. Seed yield was the highest (1700 kg ha-1 ) in v1f4 during Rabi. Haulm yield and TDMP recorded were higher for v1f4 and was on par with v2f4 during both the seasons. The available N status in soil was higher during both the seasons in v1f4 with the highest NPK uptake during Rabi. Sumanjana and DBGV 5 with f4 realized higher mean net income (₹ 70411 ha-1 and ₹ 61256 ha-1 ) and mean B: C ratio (2.04 and 1.95). The present study identified DBGV 5 and Sumanjana as shade tolerant blackgram varieties with superior growth and yield attributes under partial shade and could be recommended for intercropping in coconut garden. Further, the yield of the shade tolerant varieties could be enhanced by recommended dose of nutrients as per KAU package supplemented with foliar spray of 19:19:19 (1%) at 45 and 60 DAS + foliar spray of NAA 40 mg L-1 and SA 100 mg L-1 at preflowering (35 DAS) and 15 days later. Sumanjana and DBGV 5 raised under partial shade in coconut garden with recommended dose of nutrients supplemented with the above said foliar spray realized higher mean net income and mean B: C ratio.
  • ThesisItemOpen Access
    GIS integrated site-specific fertigation recommendations for Instructional farm, KCAET, Tavanur
    (Department of Irrigation and Drainage Engineering, KCAET, Tavanur, 2021) Subhasree, N; Sajeena, S
    Excessive application of fertilizers can cause wastage of fertilizer which increases input cost and environmental pollution. Implementation of Precision Agriculture through site specific nutrient management is the best suitable solution to increase nutrient application efficiency and thereby increase crop productivity. Site Specific Nutrient Management (SSNM) is the real time feeding of crops with nutrients while recognizing the spatial variability within the fields. In this context a study on “GIS Integrated Site-Specific Fertigation Recommendations for Instructional Farm, KCAET, Tavanur” was conducted. Delineation of the study area was done with the help of cadastral map of KCAET campus and coordinates of the corner of the study which were found using hand held GPS during the study. Sampling points were located by using gridding tool. The soil samples were collected at the 40 sampling points and analysed for the soil chemical properties such as pH, Electric Conductivity, Available Nitrogen, Available Phosphorous, Available Potassium, Boron and Sulphur by using standard methods. Spatial variability maps of soil chemical properties were prepared by using Inverse Distance Weighing method of interpolation tool in spatial analyst tool of Arc tool box in ArcGIS. Based on soil analytical values, site specific nutrient recommendations were calculated to each grid for Coconut, Banana and different vegetables by Site Specific Soil Nutrient Calculator (SSSNC). It is a winForm Windows application created with the help of Objective-C using Visual studio 2019. Based on nutrient index rating given by Meena et al., (2006), potassium and phosphorous were found in the range of ‘medium fertility’ (1.67-2.33), nitrogen and sulphur were under ‘low fertility’ (<1.67) and boron was found to be under high fertility range (>2.33) in the study area. According to the criteria given by Wilding et al., (1985), pH was found to be least variable whereas nitrogen and boron were moderately variable and the remaining parameters such as organic carbon, phosphorous, potassium and sulphur were found to be most variable parameters in the study area. The maps and the Site-Specific Soil Nutrient (SSSN) App which were developed during the study will help farmers to make better site-specific nutrient recommendations. From this study, it can be concluded that implementation of site-specific fertigation recommendations can eliminate the excessive application of fertilizers and a significant amount of fertilizer can be saved when compared to Package of Practice/ adhoc recommendation.
  • ThesisItemOpen Access
    Development and evaluation of small scale hydroponic green fodder production system
    (Department of Soil and Water Conservation Engineering, KCAET, Tavanur, 2021) Adarsha Gopalakrishna Bhat; Jinu, A
    A research on development and evaluation of small scale hydroponic green fodder production system was conducted in PFDC building of Kelappaji College of Agricultural Engineering and Technology Tavanur. The objective of research work was to develop a small scale hydroponic green fodder production system, testing of developed system under different micro climatic condition and estimation of water use efficiency for different water application method. Three different water application methods mist (I1), micro sprinkler (I2), fogger (I3) were selected. Artificial light source of LED red (L1), LED blue (L2), LED red + blue (L3) and sunlight were taken for the study. Statistical analysis was conducted to understand the significance of different treatments used in the experiment. A working prototype with best treatments observed during the study was built and cost economics were studied. The highest yield was observed in treatment involving fogger irrigation and LED red + blue (2.11 kg/tray) with the highest water use efficiency (515.43 kg/m3 ) compared to other treatments. The results are in accordance to the results found by Bian et al., (2018) and Kobayashi et al., (2013), who also found the highest yield under the combination of red + blue LED. Seed to fodder ratio obtained was 1: 6. Chemical analysis showed higher percentage of crude protein (13.56%) and crude fibre (12.59%) in this treatment. Higher growth of green fodder under artificial light source can be attributed to the continuous supply of energy compared to highly varying sunlight and also the uniform distribution of water by fogger irrigation which maintained favourable condition for fodder growth. Results clearly shows that growing green fodder with artificial light source (LED red + blue) and water supply with fogger can be commended to farmers for achieving better growth of green fodder for domestic animals.
  • ThesisItemOpen Access
    On-farm evaluation of selected cereal fodders in prominent land use systems of Kerala
    (2021) Shahina, N N; Asha K Raj
    The field study entitled “On-farm evaluation of selected cereal fodders in prominent land use systems of Kerala” was carried out as two separate experiments in homegarden and coconut garden with livestock component in Madakkathara panchayath, Thrissur, Kerala during 2020-21. The study aimed to evaluate the forage yield and nutritive value of three cereal fodders viz., maize, sorghum, and bajra in major land use systems of Kerala viz., homegarden, coconut garden, and under open conditions with full sunlight. The study also assessed the relative performance of cereal fodders with hybrid napier, the popular fodder grass in Kerala. In each system, the treatments were laid out in Randomized Block Design replicated three times. The crops were cultivated during two different seasons viz., rabi and summer. In homegarden trial, all the crops established well in homegarden and contiguous open areas. In general, the growth parameters of crops were better in the open field. Among crops, maize showed better growth followed by hybrid napier, bajra, and sorghum. In open field, maize recorded significantly higher cumulative green fodder yield (93.27 Mg ha-1 in rabi and 93.32 Mg ha-1 in summer) followed by hybrid napier (70.42 Mg ha-1 in rabi and 79.20 Mg ha-1 in summer), while in homegarden, the yield of maize (57.16 Mg ha-1 and 73.50 Mg ha-1 ) and hybrid napier (60.42 Mg ha-1 in rabi and 73.51 Mg ha-1 in summer) was on par. The productivity of sorghum and bajra was poor in both land use systems. The shade tolerance of fodder grasses in homegarden is in the order; hybrid napier>maize >bajra >sorghum. Dry fodder yields also followed a similar trend. The fodder production was generally higher during the summer season than in rabi. The per day productivity was higher for bajra and maize in both land use systems. The PAR availability in homegarden as compared to open conditions during rabi and summer season was 31.72 and 49.18 percent respectively. Considering the quality aspects of fodder, the crude protein content was higher and crude fibre content was lower in homegarden than in open field, whereas xvii the dry matter and ash content showed the reverse trend. In homegarden and open field, maize had more crude protein content followed by hybrid napier, bajra, and sorghum during both seasons. The order of CF content in homegarden was in the order; maize maize > bajra > sorghum. The dry fodder yields also followed a similar trend. Per day productivity of fodder grasses was noticed more in open contiguous areas as compared to coconut garden. The maximum per day productivity was obtained by bajra and maize in both land management systems. The mean daily PAR transmittance in coconut garden during the rabi and summer season was 55.74 and 56.83 percent respectively. In the second experiment also, the crude protein content was higher and crude fibre content lower in coconut garden, whereas the dry matter and ash content observed more in open fields. In coconut garden, maize had more crude protein content followed by hybrid napier and the crude fibre content was minimum in maize. The ash content was also maximum in maize. The grasses in the coconut garden showed more N content and were recorded highest in maize. The P and K content recorded higher values in open conditions than in coconut garden. The P concentration was maximum in hybrid napier, while K content was highest in fodder bajra. In both systems, maize recorded the highest B: C ratio followed by hybrid napier. xviii Thus, the study indicates that cereal fodder, maize can be successfully and cost effectively cultivated in partially shaded tree-based systems like homegardens and coconut gardens with minimal yield loss. In comparison, yield reduction was higher under homegarden with low PAR transmission (41 percent) than that of coconut garden with higher light availability (56 percent). The study also indicated that maize outperformed hybrid napier both quantitatively and qualitatively under coconut garden with more availability of light, whereas it showed a comparable response in homegarden with intense shade indicating higher shade tolerance of hybrid napier. Bajra showed moderate performance under shady situations whereas sorghum yielded very poor results.