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Open Access
Comparative micromorphologial and physico- chemical study of the upland and midupland laterite soils of Kerala
(Department of soil science and agricultural chemistry, College of Agriculture, Vellayani, 1986) Sankarankutty Nair, R; KAU; Aiyer, R S
Open Access
Exchangeable aluminium as an index of liming for the acidic upland soils of Kerala
(Department of soil science and agricultural chemistry, College of Agriculture, Vellayani, 1987) Meena, K; KAU; Alice, Abraham
Aluminium toxicity is the major factor limiting crop production in the acidic soils and the usual practice of alleviating aluminium toxicity is liming* / The present investigation was carried out to find out the distribution of water s dluhle and exchangeable aluminium in the acidic upland soils of Kerala and to test the suitability of exchangeable aluminium as an index for liming them* It was further programmed to find out the growth, yield and nutrient uptake pattern of two acid sensitive crops namely cowpea and fodder maize in soils under different levels of exchangeable aluminium brought out by the use of different levels of lime* Chemical analysis of eighty soil samples representing the five major upland soil types of Kerala viz* laterlte, alluvial, red loam, sandy and forest a oil have indicated the highest amount of exchangeable aluminium and percentage aluminium saturation in the laterite soils* The soil with 3 high level of exchangeable aluminium and percentage aluminium saturation was selected for conducting a pot culture experiment to test the suitability of using exchangeable aluminium as an index of liming* The exchangeable aluminium content of this soil was maintained at different levels by applying different levels of lime and the performance of these crops in this soil was compared by making biometric observations and by chemically analysing plant and soil samples* From the results of the study it was seen that higher levels of exchangeable aluminium adversely affected the growth, yield and nutrient uptake In cowpea and fodder maize* Maintenance of exchangeable aluminium at 1*26 me/100 g with a corresponding percentage aluminium saturation valua of around 30, by the use of 500 kg lime/ha appeared to be the optimum for maximising the yield of cowpea* But in fodder maize this level of lime was found to be insufficient and complete elimination of aluminium toxicity appeared to be essential for maximising production* Since the critical levels of exchangeable aiuainiua appears to be different for different crop3, it is desirable that lias levels to reduce exchangeable aluminium to such a critical level alono be applied. The results of the present study thus point to the advantage in adopting the exchangeable aluminium level of soil as a better index of liming for various crops grown in the upland acidic soils of Kerala.
Open Access
Forecasting models for crop yield in cashew (anacahdium occident ale l.)
(Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1987) Usha, Menon R; KAU; George, K C
Open Access
Estimation of induced variability in chillies
(Department of agricultural botany , College of agriculture Vellayani, Trivandrum., 1985) Lekha Rani, C; KAU; Krishnan Nair, N
The mutagenic effect of Co-gamma rays and Ethylmethane sulphonate on three different chilli varieties have bean studied in detail in generation U3 ing two moderate doses of gamma rays <20 and 30 kR) and two concentrations of ISMS (0.5 and 1*0 par cent)* The presence and extent of chimeras and their relation to induced variability was assessed by raising branch-wise progenies in ^ generation* The experiment was conducted during 1982-84 at the Department of Agricultural Botany# College of Agriculture, Vellayani* The generation was laid out in RBD and in splitplot design with proper randomisation and replications* The crop wa3 raised and maintained following the Package of Practices recommended. The polygenic traits analysed in a, generalisen include plant height, number of branches per plant, fruit yield per plant and length and weight of fruits. The data collected were statistically analysed for proper interpretation of tho results obtained. It has been observed in almost all the polygenic traits that the extent of variability created vary depending on the genotypes, mutagen and their dosos and character under observation. The mean values wer« found to shift both in negative and positive directions to control values• significant shift in mean values depending on the type of branch category clearly demonstrates that there exists the mechanism of diplontlc selection in this particular crop variety# when exposed to mutagens. But the extent of selection varies depending on the mutagen and their doses and the genotypes concerned. a significant negative shift in mean Value was noted only in the case of fruit weight under both the concentrations of EM3 and 20 kR gamma rays whereas a positive or negative insignificant shift was noted in all other characters under both the mutagens, when under EM3 and in gansna rays showed a negative shift* positive shift in mean value wes noted in majority of the cases for number of branches per plant. Fruit length and weight and number of seeds per fruit showed a negative shift in majority of the cases analysed# but fruit number and yield per plant showed a reverse trend. The shift in mean value under the different branch categories varied depending on the varieties# mutagens and their doses and also the character under study. The phenotypes were found toAdistributedboth in negative and positive directions to control group in all the characters analysed. The frequency distribution whether negative or positive varied depending on the mutagen and their doses# the genotypes and character under study. In majority of tha cases the maximum frequencies of positive variants under both the concentrations of EMS and under 0.5 per cent for negative variants were found to be in the early formad branches when it was in the later ones is tha case of negative variants under 1.0 per cent EMS. in the case of gamma rays this general trend was not observed* The data analysed clearly demonstrate the existence of diplontic selection and promises wide scope for positive selection response either in negative or positive directions.
Open Access
Study of genetic correlations under full -SIB mating system (Two loci case)
(Department of Statistics, College of veterinary and animal sciences Mannuthy, Thrissur, 1985) Khin Moe Moe; KAU; George, K C
A purely theoretical investigation entitled ,JA Study of Genetic Correlations under Fu ll-s ib Mating System (two lo c i case)*1 was carried out with the following objectives, i ) to derive the joint distribution (correlation table) and to find the correlation between fu ll -s ib pairs under fu l l -s ib mating system in the case of two lo c i when there i s no linkage as well as when there i s complete linkage. l i ) to derive the joint distribution (correlation table) and to find the correlation between parent-offspring pair© under fu l l -s ib mating system in the case of two loci when there is no linkage as well as when there is complete linkage, i i i ) to derive the joint distribution (correlation table) and to find the correlation between fu l l -s ib pairs under paront-offspring mating system in the case of two lo c i when there is no linkage as well as when there is complete linkage, iv) to derive the joint distribution (correlation table) and to find the correlation between parent-offspring pairs under parent-offspring mating system in the case of two lo c i when there is no linkage as well as when there is complete linkage. 2 Th© joint distributions of fu ll -s ib pairs and parent- ©Ffspring pairs undor fu ll-s ib gating system wore derived with the help of generation matrix technique and th© correlations wore worked out therefrom, assuming additive genie e ffec ts and using the product-momeni correlation coefficient formula. The correlations were worked out for tho f i r s t ten generations of fu ll -s ib mating in both cases of no linkage and complete linkage, & comparative study of fu ll -s ib correlations and parent-offspring correlationsf conducted both numerically and graphically, revealed that £i) evonthough fu ll -s ib correlation was greater than parent-offspring correlation in in i t ia l generation (random mating) when there was complete linkage, the la tte r increased more rapidly than the former from in it ia l generation to f ir s t generation and ( i i ) from the second generation onwards, the rate of increase in both o f correlations were nearly the same upto tenth generation. I t was interesting to note that the parent-offspring correlations wore of comparatively higher order than th© fu ll-s ib correlations in both cases of complete linkage and no linkage. Similarly, th© joint distributions (correlation tables) for fu ll-s ib pairs and parent-offspring pairs under parentoffspring mating system were derived employing generation matrix approach and the correlations for the f i r s t ten 3 generations of parent—offspring mating in both cases of no linkage and complete linkage were worked out therefrom. A comparative study of those correlations was carried out both numerically and graphically. It was found that the trend in both correlation curves remain the same, but the value of parent-offspring correlation was always greater than that of full-sib correlation in case of no linkage as well as in caso of complete linkage. In comparison of all these correlations, it was found that the correlations increased as the number of generation increased and ultimately reached the limit unity when the number of generations increased indefinitely large. It was also observed that the magnitude of correlation in case of complete linkage was more than that of correlation In case of no linkage even under the same system of mating*
Open Access
Impact of the coconut rehabilation programme of SADU in Trivandrum district
(Department of Agricultural Economics, College of Horticulture, Vellanikkara, 1984) Lekshmi Narayanan Nair, N; KAU; Radhakrishnan, V
This study was conducted in 1983 to assess the impact of the Coconut Rehabilitation Programme implemented in Trivandrum District as part of the World Bank assisted, Kerala Agricultural Development project. The specific objectives were to examine the extent of utilization of loans, the improvements in cropping pattern and farming practices, changes in yield rates and output and the increase in farm income generated by this programme. The relative efficiency of irrigation and the various intercrops in augmenting the net farm incomes of the participating farmers was compared and the major constraints in improving coconut farming in the district were also identified as a part of this study. Data were collected from a sample of 96 participating farmers selected at random from the 14 Package Units functioning in the district under this project through personal interview using a well structured schedule. The main findings of the study are summarized below. Majority of the holdings (51.03 per cent) were in the category of less than 0.80 hectare but they accounted for only 27.36 per cent of the area covered. Holdings of 0.80 hectare and above predominated (59.26 per cent) in the category of irrigated holdings. About 49 per cent of the households depended on non-agricultural pursuits for their main source of income. Eighty per cent of the families were relatively small in size with a membership of less than 7. The overall average investment estimated, sanctioned and spent per hectare for the 96 holdings under study worked out to Rs. 17923.05, Rs.14393.67 and Rs.14959.57 respectively. Though the overall performance in respect of loan utilization was satisfactory, there was shortfall in utilization of loans under Cocoa (58 per cent), coconut gapfilling (41 per cent), purchase of Cows (23 per cent) and Fodder Development (17 per cent). The percentage of utilization of loans in the case of unirrigated category was low (50.18) compared to the irrigated category (122.43). Among the lending institutions through which the National Bank for Agriculture and Rural Development funds were channelised, Primary Co-operative Land Mortgage Bank was the most acceptable agency (61 per cent). The cropping intensity of the sample increased from 111.77 per cent to 189.87 per cent consequent on the implementation of the programme. The area under coconut, banana, cocoa and fodder increased while that under tapioca decreased. The density of coconut palms increased from 125 palms per hectare to 176 palms. This is against the project objective of attaining an optimum stand of 175 healthy and high-yielding coconut palms. By and large the target set for intercropping programme as per the individual farm production plans has been achieved. The target was exceeded in respect of banana (119.3 per cent) coconut (103.34 per cent) and cocoa (101.2 per cent). Tapioca continued to be the intercrop widely preferred by the coconut growers (192.75 per cent). Shortfall was mainly in the coverage of area under fodder (18 per cent) and livestock to be purchased (36 per cent). The project has been instrumental in stepping up substantially the level of use of various inputs including irrigation. Fifty four holdings had the benefit of irrigation covering 62 per cent of the net area covered by the sample, while in 13 cases though irrigated development was contemplated, it had not been successful due to operational constraints such as failure to obtain electric connection, failure of wells etc. The average cost of a pumpset with accessories worked out to Rs. 8717.68 while the average amount sanctioned under the lending programme was only Rs.7715 per pumpset. The intensity of senile and uneconomic palms as revealed by the study was only 3.6 palm per hectare against the projection of 20 palms per hectare assumed in the project report. Out of 388 palms identified for cutting and removal only 77 were actually removed. Though the target in respect of gap filling has been exceeded by planting 4790 seedlings against the target of 4762 seedlings, the maintenance of the seedlings was not upto the standard. The increase in use of organic manure for coconut from 17 to 48 kg per palm is commendable. But the use of organic manure for the intercrops is deplorably low especially for banana (6 kg per plant) cocoa (3 kg per plant) fodder (2200 kg per hectare) and tapioca (3698 kg per hectare). Fertilizer application for coconut has increased from 0.22 kg to 1.52 kg per palm. The average fertilizer dose of 0.08 kg per cocoa plant 0.25 kg per banana plant, 33 kg per hectare for fodder and 113 kg per hectare for tapioca as adopted by the participants were also inadequate. Only 6 out of 96 holdings covered under the survey have adopted plant protection measures. The intensity of cultural practices has increased many fold with the biggest increase for coconut (562 per cent). All the crops except tapioca have registered substantial increase in total production. Banana, coconut and milk production registered increases of 677 per cent, 62.45 per cent and 15 per cent respectively. Production of tapioca declined by 25.6 per cent. The increase in productivity of coconut was only 38 per cent over the productivity at the pre-project level. In absolute terms the productivity of coconut has increased from 25 nuts to 30 nuts per palm in the unirrigated holdings while the increase in irrigated holdings was from 30 nuts to 44 nuts per palm. The overall increase was from 29 to 40 nuts for the sample as a whole. The increase in yield was highest in the holdings which have completed 5 years (67 per cent) of development followed by holdings completing 4 years (31 per cent) and 3 years (29 per cent). The post project average yield of intercrops such as cocoa (Rs.59 per hectare) banana (6.95 kg per plant) fodder (4525 kg per hectare) and tapioca (5055 kg per hectare) was considerably low. The average gross income per holding increased from Rs.4478 to Rs.9224. In per hectare terms the increase was from Rs.4613 to Rs.9502 (105 per cent). The average net farm income rose from Rs.2860 to Rs.3821 per hectare (34 per cent). The increase in net farm income was maximum in the case of holdings which had completed 5 years of development (69 per cent) followed by holdings completing 4 years (32 per cent) and 3 years (20 per cent). An increase of 47 per cent in the average yield of coconut, 62 per cent in fodder, 0.47 per cent in banana, 134 per cent in cocoa and 17 per cent in milk was notices under the irrigated holdings over the unirrigated holdings. Comparative analysis of the different intercrops indicated that banana is the most profitable intercrop in coconut gardens in Trivandrum district with a potential net return of Rs.6015 per hectare. Mixed farming with dairying as one of the components, though successful in holdings of more than 0.8 hectare size, ranks only second in order of profitability, with a net income of Rs.2990 per hectare. Tapioca with an average return of Rs.621 per hectare ranks third in the order of profitability. Cocoa, the fourth intercrop compared showed negative returns at the yield and price levels prevailed. Economic uplift of the coconut growers by augmenting farm income through whole farm development approach had been the basic objective of the project. On the whole the project has made a good beginning in this direction in spite of several operational constraints.
Open Access
Effect of growth regulators on flowering pollination and seed-set in ginger(zingiber officinale, rose)
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1984) Usha, K; KAU; Balakrishnan, S
Flowering behaviour and floral biology of Rio-de-Janeiro and Maran and the effect of growth regulators viz., kinetin (5, 10 and 15 ppm), Ethrel (25, 50 and 100 ppm) and NAA (10, 25 and 50 ppm) in combination with two per cent urea and without urea on flowering, pollination and seed-set in Rio-de-Janeiro were studied at the College of Horticulture, Kerala Agricultural university, Vellanikkara during 1981-’83. The objective of the investigation was to assess the available varieties of ginger for flowering behaviour and to evaluate the effect of growth regulators with and without urea on the flowering behaviour, floral biology, floral structure, pollination and seed- set in Rio-de-Janeiro. (The possibility of overcoming the problems of shy and irregular flowering, poor pollen germination and the failure to set seeds also was explored during the investigation). (Among the 25 varieties studied, flowering was observed only in two varieties viz., Rio-de-Janeiro and Maran). Considerable variation was noticed between Rio-de-Janeiro and Maran with respect to flowering behaviour, extent of flowering, types of inflorescence, time taken for scape development, anthesis, anther dehiscence, pollen production, pollen fertility, style length and ovary length. Long but thin style was noticed both in Rio-de-Janero and Maran. Irrespective of the variety, flowers were found to rot/ and dry within 16 hours after flower opening. The maximum pollen germination (6.20 per cent) was obtained in the medium containing eight per cent sucrose, three per cent gelatin and 60 ppm boric acid under moist cotton covering in BOD incubator (26.50C). Coiling of the pollen tube during the advanced stages of growth was noticed. Pollination carried out in Rio-de-Janeiro and Maran employing the variables like stage of flower (bud stage, immediately after flower opening and three hours after flower opening), condition of stigma (partial and complete removal of style), density of pollen (smearing once, twice and thrice with standard brush), mixed pollen (ginger pollen with either Alpinia, Hedychium, Kaempheria or Costus pollen) and supplementary pollination (repeated pollination twice at two hours interval) failed to record any positive evidence of seed-set. Effect of growth regulators and urea on flowering behaviour, inflorescence characteristics and floral structures of ginger was evidenced during the study. ( Favourable influence of NAA 50 ppm on inducing early flowering, kinetin 15 ppm on the duration of flowering, NAA and kinetin on inflorescence production, NAA 50 ppm without urea on the number of flowers per inflorescence, NAA 10 ppm and all the three levels of kinetin on pollen production, NAA on pollen diameter, higher levels of Kinetin and Ethrel and lower levels of NAA on exine thinning, Ethrel 25 ppm in combination with urea, Kinetin 15 ppm with urea, NAA 50 ppm and Kinetin 10 ppm on pollen fertility, lower levels of Kinetin and Ethrel on reducing the style length, Kinetin 15 ppm and NAA 10 ppm on ovary length, Ethrel 25 ppm with urea and higher levels of NAA and Kinetin on pollen germination and NAA 50 ppm on pollen tube growth was revealed during the study.) Floral biology of Rio-de-Janeiro was not influenced by growth regulator and urea treatments. Abnormal floral structures occurred as isolated cases and therefore the role of growth regulators and urea in this respect was not clear from the results. (Pollination carried out in ginger (var.Rio-de-Janeiro) plants, subjected to growth regulator treatments with and without urea, employing the variables like stage of flower, condition of stigma, density of pollen, mixed pollen and supplementary pollination failed to result in seed-set.)
Open Access
Economics of coconut cultivation in Calicut district
(Department of Agricultural Economics, College of Horticulture, Vellanikkara, 1987) Premaja, P; KAU; Mukundan, K
A study on the economics of coconut cultivation in Calicut district was conducted during the period 1985-86, to evaluate the costs and returns, capital productivity, resource use efficiency of yielding plantation, the problems of coconut cultivators and the impact of incentives given by different agencies for coconut cultivation. Three stage random sampling was adopted for the study and data were collected from a sample of 120 cultivators by personal interview method. Coconut was cultivated mostly in small holdings and the average area under coconuts in the sample was 0.24 hectare. Most of the holdings were rainfed. Total cost of cultivation for 16 years was estimated to be Rs. 91,311 for the district, in terms of 1985-86 prices. The major item of expenditure was human labour constituting about 50.49 percent of the total cost. Fertilisers including farm yard manure accounted for 24.16 percent and harvesting charges for 9.90 percent of the total cost for 16 years. The total cost of bringing one hectare of coconut plantation up to bearing stage (initial 7 years’ expenditure) was estimated as Rs.38,773 and the maintenance cost per hectare per year was Rs.5,853. The average annual production of nuts per hectares during the stabilized period was estimated as 10049 nuts. Cost of production per nut was calculated as Rs.1.12. The estimated net returns on investment per hectare per year come to Rs.13,835 based on 1983-84 prices. Pay back period was found to be 13.18 years. Benefit cost ratio was calculated as 1.44. Net present worth was Rs.24.454 and internal rate of return was calculated to be 16.39 percent. The factors age, labour, fertilizer and plant protection were found to have significant influence on the gross income obtained from a coconut garden. High input costs, poor irrigation facilities and difficulties associated with marketing were some of the general problems faced by the sample farmers. The study showed that in general, incentives and subsidies given by different agencies have had very little impact on coconut cultivation in the study area.
Open Access
Varietal screening of banana against anthracnose disease
(Department of Plant Pathology, College of Horticulture, Vellanikkara, 1984) Srinagesh, K L; KAU; Jose, P C
Laboratory and field studies of the varietal screening of banana against anthracnose disease were conducted at the college of Horticulture. Vellanikkara and at Banana Research Station, Kannara respectively during 1981-1983. In the field the infection started at the distal end of the banana fruit and in course of time the infected fruit became blackened, shriveled and mummified. After Harvest, the symptoms appeared as small brown spots which enlarged quickly and coalesced forming larger patches. The affected areas were covered with orange to salmon pink coloured conidial masses. The detailed morphological studies of the fungus proved that the anthraemose disease of banana is caused by colletrichum cloeosporioides cooko and massee, the imperfect stage of glomerella cinoulata spauld and shrenk. Twenty five varieties of banana fruit were screened in vitro at different stages of development against anthracnose disease. The varieties showed different degrees of susceptibility at various developmental stages of the fruit. The pooled analysis of the data showed that the variety nendra padaththi followed by palayankodan, jurmani kunthali, boodida bontha bathes, peyan, kanchikela, pisang mas and kapok were found to be highly resistant. The varieties Zanzibar, adakka kunnan, klue teparod, chinia, nendran, venneettu mannan, koduppilla kunnan, hybrid sawai, poocha kunnan, red banana and boodles altafort were found to be resistant to the disease. The variety robusta was found to be susceptible. The varieties njalipoovan, pisang lilin, dwarf Cavendish, matti and gros Michel were found to be highly susceptible. The major chemical constituents of banana fruit viz. reducing sugars, total sugars starch, crude fibre, crude protein and tannin at different developmental stages of twenty five varieties were analysed. The reducing sugars and total sugar were found to increase steadily from immediately after female phase to ripened stage in all the varieties. The starch and crude fibre contents, though increased steadily upto full maturity. Declined sharply at the ripening stage. The crude protein and tannin contents were maximum at immediately after female phase but steadily decreased and were minimum at ripening phase. There was a significant positive correlation between reducing sugars, total sugars and per cent disease intensity at three fourth maturity. High sugars were responsible for susceptibility to the disease. A significant negative correlation was obtained between crude protein and per cent disease intensity at half maturity. A significant negative correlation was also obtained between tannin and per cent disease intensity at one fourth and half maturity stages. High crude protein and high tannin contents were responsible for resistance to the disease.

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