1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)

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Role of Piriformospora indica in mitigating drought stress in watermelon (Citrullus lanatus (Thumb.) Mastum. & Nakai)
(Department of Vegetable Science, College of Agriculture,Vellanikkara, 0018-03-24) Jyothymol, C P.; Sangeeta Kutty, M
Watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) is a tropical crop of high economic and nutritive value that belongs to the Cucurbitaceae family. Water availability during the critical growth stages significantly influences both the yield and quality of watermelons (Nisha and Sreelathakumari, 2020). Prolonged drought stress in watermelon ultimately results in the dropping of flowers and fruits, resulting in decreased fruit yield (Mo e t al., 2016). Piriformospora indica is a beneficial root endophytic fungus that is reported to enhace plant tolerance to such abiotic as well as biotic stresses. In this study, we have evaluated the influence of P. indica in mitigating drought stress in watermelon. The study was conducted in a poly house located at the Department of Vegetable Science, COA, Vellanikkara. The experimental design was factorial CRD (Completely randomised design) with three replications and it consists of three factors each at two levels. The first factor involved in the study was variety. Two varieties namely, ‘Thar Manak’, which is the only reported drought tolerant variety of watermelon released from CIAH, Bikaner and the drought susceptible variety Sugarbaby released from IARI, were used in this study. Factor two consists of two levels of irrigation (35% field capacity and 75% field capacity). The third factor was colonization (Colonized with P. indica and non colonized with P. indica). These two varieties of watermelon were induced to soil moisture stress at different field capacities, both after colonizing with P. indica and without colonizing with P. indica. Drought stress was imposed three weeks after transplanting by gravimetric method (Mo et al., 2016). Observations were recorded after five days of drought imposition. The experiment was conducted for two seasons ie., May June and October-November. In both the seasons, all the root characters such as root length, root hypocotyl diameter, root fresh as well as dry weight was found to be significantly higher in P. indica colonized Thar Manak at 35 per cent field capacity. The vine length, shoot fresh weight and dry weight was found to be higher in P. indica colonized seedlings when compared with non-colonized ones. Highest root to shoot ratio was observed in P. indica colonized Thar Manak at 35 per cent field capacity (0.082 and 0.054 in the first and second season respectively). The results obtained over the two seasons revealed that during drought stress (35% FC), the highest transpiration rate, stomatal conductance, photosynthesis rate, instantaneous and intrinsic water use efficiency were observed in P. indica colonized seedlings of both varieties than their non-colonized seedlings. P. indica colonization has helped in lowering the rise in surface leaf temperature during drought stress. The highest RWC was observed in P. indica colonized Sugarbaby at 75 per cent field capacity (89.58 %) followed by P. indica colonized Thar Manak at 75 per cent field capacity (87.15 %) in both the seasons. Drought stress induced decrease in the leaf chlorophyll and carotenoid content was found to be lower in P. indica colonized seedlings when compared with the non colonized ones. In both seasons, the highest proline and catalase activity was observed in P. indica colonized Sugarbaby at 35 per cent field capacity. Results of DAB staining demonstrated more accumulation of harmful H2O2 in non-colonized seedlings during drought stress when compared with colonized ones. P. indica colonization has aided in enhancing the DPPH free radical scavenging activity during drought stress. It was observed that most of the treatment combinations showed significant seasonal variation in the expression of majority of this drought tolerance traits. The average temperature and relative humidity recorded during the stress period was around 41.80 ℃ and 72.00 % respectively in the first season and 43.86 ℃ and 53.60 % respectively in the second season.The varietal influence of P. indica in imparting drought stress tolerance has also been evaluated and was observed that the influence of the fungi was more pronounced in Sugarbaby. The influence of P. indica in combating drought stress was more evident in a drought susceptible variety of watermelon than a tolerant variety
Integrated weed management in cowpea (Vigna unguiculata L.)
(Department of Agronomy, College of Agriculture,Pdanakkad, 19-04-04) Amaya, C P; Gayathri Karthikeyan, P
Standardisation of seed biopriming for seedling establishment, growth, yield and nutritional characters in tomato (Solanum lycopersicum L.)
(Department of Seed Science and Technology, College of Agriculture, Vellayani, 0022-02-01) Diya Amreen; Beena R
The present study entitled “Standardisation of seed biopriming for seedling establishment, growth, yield and nutritional characters in tomato Solanum lycopersicum L.). was conducted in the Department of Seed Science and Technology, College of Agriculture, Vellayani, Kerala during 2020-21. The objective of this study was to standardize the biopriming methods in tomato for germination, seedling vigour, yield and nutritional characteristics using three biopriming agents Trichoderma asperellum 106 spores mL-1and 108 spores mL-1), Pseudomonas flourescens 106 CFU mL-1 and 108 CFU mL-1) and Piriformospora indica 106 spores mL-1 and 108 spores mL-1) for one and two hours. The study was divided in to two experiments. Experiment I was conducted in Completely andomized Design C D) with fourteen treatments and three replications. During experiment I germination studies were conducted using roll towel method. Best three treatments were selected from experiment 1 based on the germination parameters. Experiment II was also conducted in Completely andomized Design with five treatments and four replications. The pot culture experiment was conducted to evaluate the effect of these best three treatments on phenological, physiological, growth, quality, biomass and yield parameters. During experiment I, among various treatments employing T. asperellum, T2 T. asperellum 106 CFU mL-1 for two hours) recorded the highest germination percentage 88.67 ), shoot length 7.60 cm), root length 6.39 cm), shoot dry weight 0.92 mg), root dry weight 0.45 mg), seedling vigour index 1 1240.09), seedling vigour index II 121.30) and speed of germination 7.28). On biopriming with P. flourescens T8 P. flourescens 108 CFU mL-1 for two hours) reported the maximum germination percentage 86.67 ), shoot length 7.56 cm), root length 7.63 cm), shoot dry weight 0.91 mg), root dry weight 0.45 mg), seedling vigour index 1 1316.26), seedling vigour index II 117.54) and speed of germination 7.23). On biopriming with P. indica maximum germination percentage 91.33 ), shoot length 7.67 cm), root length 7.82 cm), shoot dry weight 0.97 mg), root dry weight 0.54 mg), seedling vigour index 1 1414.73), seedling vigour index II 137.46) and speed of germination 7.68) was obtained from seeds bioprimed with P. indica 106 CFU mL-1 for one hour. Based on the above results the best three treatments selected were T. asperellum 106 CFU mL-1 for two hours T1), P. flourescens 108 CFU mL-1 for two hours T2) and P. indica 106 CFU mL-1 for one hour T3) along with appropriate control. Then pot culture experiment was conducted to evaluate the effect of these three biopriming treatments on phenological, physiological, growth, quality, yield and biomass parameters. Among the phenological parameters days to first flowering and days to first fruiting was minimum in T3 P. indica 106 CFU mL-1 for one hour) 51.92 and 78.75 days respectively). Biopriming with P. indica 106 CFU mL-1 for one hour T3) recorded the maximum physiological and growth parameters including chlorophyll content 2.82 mg g-1 fresh weight), specific leaf area 3.96 m² g-1), crop growth rate 0.912 g m-2 day-1) and net assimilation rate 0.027 g m-2 day-1). Among the various quality parameters analyzed, there was no significant difference observed for TSS and soluble sugar content. Highest Lycopene content 2.81 mg g-1) and vitamin C 35.56 mg g-1) content was noted in T3 P. indica 106 CFU mL-1 for one hour). Highest titrable acidity 0.68 ) was recorded in T1 T. asperellum 106 CFU mL-1 for two hours). Plant height was also maximum in T3 P. indica 106 CFU mL-1 for one hour) during vegetative 80.20 cm) and flowering stages 127.37 cm). Biopriming with P. indica 106 CFU mL-1 for one hour recorded the maximum shoot dry weight 8.31g), root dry weight 0.97 g) and total dry weight 9.28 g). There was no significant difference observed in root shoot ratio. The yield parameters including number of fruits per plant 7.25 ), fruit set percentage 56.78 ), average fruit weight 36.60 g) and yield per plant 263.56 g) was maximum in T3 P. indica 106 CFU mL-1 for one hour).The intensity of fruit drop 4.96 ) was minimum in T3 P. indica 106 CFU mL-1 for one hour). Biopriming is reported to have exerted significant influence on the growth, yield and nutritional characters of tomato. Among various biopriming agents P. indica 106 CFU mL-1 for one hour outperformed T. asperellum and P. flourescens in improving phenological, physiological, growth, quality, biomass and yield parameters. Thus being an eco-friendly technique, the farmers can adopt biopriming with P. indica as a great alternative for conventional chemical seed treatments.
Impact of online education during covid-19 in Kerala agricultural university:students' and teachers' perspectives
(Department of Agricultural Extension, College of Agriculture,Vellayani, 0023) Ashitha, A R.; Bindu Podikunju
Agricultural extension , Impact of online education during covid-19 The present study entitled “Impact of online learning during COVID-19 in Kerala Agricultural University: Students’ and teachers’ perspectives” was conducted in the four colleges of Kerala Agricultural University viz, College of Agriculture (CoA), Vellayani; CoA, Vellanikkara; CoA, Padannakkad and CoA, Ambalavayal. The objective was to study the perception of students and teachers about effectiveness of online education, delineation of factors affecting its effectiveness and identification of constraints therein. The sample consisted of 150 students and 40 teachers from the four colleges under KAU. Based on the judges rating and literature review, ten and eight independent variables were selected for the students and teachers, respectively. Perception of students and teachers about effectiveness of online education were selected as the dependent variable for the study. The variables were measured and analyzed with the help of various statistical tools like frequency, percentage analysis, mean, standard deviation, quartiles, chi square test, correlation and t test. The detailed investigation on the profile characteristics of students pointed out that, majority of the students (80%) were females, more than half of them (60%) belonged to rural family background and majority of them (55.8%) had medium annual income. Majority of the students (58.67%) were quite ready for the online classes during COVID-19 and most of them (86%) had self-owned devices for attending online classes. Seventy-one percentage of students had medium exposure to technology and seventy three per cent of the students used digital technology at a medium level. Majority of the students (68%) had medium adaptability with digital platforms and learning management system and nearly half of the them (46%) had fair quality of internet connection for attending online classes during COVID-19. The proportion of students who intend to continue their education online (50.67%) is marginally higher than the reverse (49.33%). Analysis of the profile characteristics of teachers revealed that majority of the teachers (65%) were female and half of them (50%) were middle aged. Majority of the teachers (65%) had less teaching experience. More than half of the teachers had prior 140 online experience before COVID-19 (60%) and had received training for taking online classes (65%). Sixty three percent of teachers belonged to the category of medium use of digital technology and majority of them (60%) had good quality internet connection for conducting online classes during COVID-19. More than half of the teachers (52.5%) had positive continuance intention for online education. The results of the study revealed that majority of the students (64%) and teachers (60%) had positive perception about effectiveness of online education. There was no significant difference observed between the perception of students and teachers about online education during COVID-19. Based on the result of chi square test, profile characteristics of students such as place of residence, annual income, continuance intention, e-readiness, exposure to technology and internet accessibility were found to have significant association with the perception of students about online education. In case of teachers, profile characteristics such as gender, age, prior online experience, training received and continuance intention had significant association with perception about online education. Among the five factors affecting effectiveness of online education viz., selfefficacy, subjective norm, attitude, digital competence and technostress, subjective norm had the highest score for students as well as teachers. Self-efficacy and attitude had positive significant correlation whereas subjective norm and technostress had negative significant correlation with the perception of students about online education. For teachers, self-efficacy and attitude had positive significant correlation whereas technostress had negative significant correlation with the perception about online education. In case of constraints in online education during COVID-19, technological and health constraints were ranked as the important constraints faced by students whereas insufficient/ unstable internet connectivity followed by the technical problems were the important constraints faced by the teachers. To conclude, students and teachers had shown interest in the use of online education in their academic activities and its use was no doubt intensified by the sudden outbreak of the COVID-19 pandemic. Even though online education had worked as an 141 aid during COVID-19, shifting completely to online mode may not be possible in agricultural education system where many courses are practical oriented. Hence, there is a need of designing a hybrid mode of education which will be beneficial for both teachers and learners during any future crisis-like situations.
Standardisation of fertigation schedule for parthenocarpic cucumber (Cucumis sativus L.) hybrid KPCH 1 under polyhouse
(Department of Vegetable Science, College of Agriculture,Vellanikkara, 23-03-08) Mintu Hanna, Reji; Dicto Jose, M
Studies on the insect pests of cardamom in Travancore
(The University of Travancore, Trivandrum, 1945) Ronga Aiyar, G
Studies on seed dormancy in rice (Oryza sativa. L.) with special reference to short duration varieties
(Faculty of Plant Breeding and Genetics, Agriculture College & Research Institute, Coimbatore, 1961) Gopinathan Nair, V; Ponnaiya, B W X
Work done in cereals and other crop plants on the factors related to seed dormancy (causes, tissues involved, stage of maturity at harvest, variation in period and genetics), which are important from a practical breeding point of view, has been critically reviewed with special reference to rice. Studies were undertaken on six short duration varieties of rice and their hybrids to estimate the period of dormancy, to understand the relative roles of the hull and the embryo and also to understand the mode of inheritance of the character. A new method was adopted in the estimation of dormancy. The period required for germination from flowering, determined by germination tests at periodic intervals, rendered a reliable estimate of inter and intravarietal variability for germination and formed the criterion for comparison of varieties and hybrids.
Breeding behaviour of interspecific hybrids in the genus Arachis L.
(Regional Post Graduate Training Centre, Agricultural College and Research Institute, Coimbatore, 1962) Gopinathan Nair, P; Ponnaiya, B W X
The investigation aims at a comparative study of two kinds of F2 populations. The first one was derived from hybrids between two tetraploid parents, namely A-hypognea and A.sp (A.354) whose genomes are homologous. The second typeof tetraploids were derived from back cross hybrids between A-hypognea and allotriploid (resulting from the cross A-hypognea X A.sp. (A.329)). A comparative morphological and cytological analysis of these F2 populations have been made. Special techniques such as Hybrid index method and Polygraphic analysis were adopted and the variability expressed in the two F2populations have been eveluated. The possible causes for the occurrence of a skewed recombination in the straight F2 population have been suggested.
Influence of Calcium and Magnesium in increasing the efficiency of fertilisers for rice and Calcium and Magnesium status of some typical rice soils of Kerala
(Division of Agricultural Chemistry, Agricultural College and Research Institute, Vellayani, 1963) Thomas Varghese; Subramoney, N
Influence of salinity on the germination and growth characteristics of rice
(Division of Agricultural Chemistry, Agricultural College and Research Institute, Vellayani, 1963) Remani, B; Money, N S
A study was made of the influence of salinity on the germination, growth and yield of different varieties of rice. Germination was studied in the laboratory for five varieties using nine salts at different concentrations. Growth and yield characteristics were observed for two varieties in a pot culture experiment by flooding the soil with sea water for twenty four hours at different stages in the growth period of the plants. The percentage germination was reduced in all the varieties with increase in the concentration of the salt. For the same concentration the adverse effects of salts on germination increased in the order ammonium chloride ammonium sulphate < sodium chloride < sodium sulphate < potassium chloride < potassium sulphate < magnesium sulphate < calcium chloride. Chlorides were generally more toxic than sulphates. Among the cations, ammonium and potassium were the least toxic, sodium and magnesium were more so, while calcium was the most injurious.
Response of CO.7 ragi (Eleusine coracana) to phosphate and potash
(Regional Post Graduate Training Centre, Agricultural College and Research Institute, Coimbatore, 1963) Ramakrishnan Nair, K
With a view to study the effect of graded doses of P2 O5 and K2O on the yield potential of popular high fertility Ragi, strain Co.7 field experiment was laid out in the Central farm, Agricultural College and Research Institute, Coimbatore during 1962-63(February). Three levels of P2O5 and K2O at 0 to 20 lb and 40 lb, alone and in combination with one level of nitrogen at 60 over a basal dressing of five tons of farm yard manure was found by analysis to have 0.38 percent P2O5 AND 0.22 percent K2O supplying 43 lb of P2O5 and 25 lb of K2O per acre.
Effect of irrigation frequencies and mulches on the yield of summer cholam (Sorghum vulgare Pers.)
(Regional Post Graduate Training Centre, Agricultural College and Research Institute, Coimbatore, 1963) Abraham Jacob, T; Mariakulandai, A
An experiment was conducted to find out the relative efficiency of three different moisture regimes, due to irrigation frequencies, at seven, fourteen and twenty one days, and three types of mulching viz., dust, trash and polythene mulches. The modifying effect of the mulches on soil conditions and crop growth was studied, to assess whether irrigation requirements could be reduced without deterioration in yield. The moisture regime had significantly increased the height of plants and length of earheads, while it had no influence on other yield attributes. Length of earhead, breadth of earhead and diameter of peduncle were significantly increased by the mulches.
Review of the insect pests of pulsecrops and studies on the biology of the pea leaf roller Nacoleia vulgalis Guence (Pyralidae)
(Division of Entomology, Agricultural College and Research Institute, Vellayani, 1963) Mammen, K V; Joseph, K V
Literature on the insect pests of the important pilse crops, with special reference to the work done in India has been reviewed. The biology and bionomics of the pea leaf roller Nacoleia vulgalis Gn. (Pyralidae) have been worked out in detail. The moths mate a day after emergence. The female moth lays creamy yellow, oval, scale like eggs during night in rows, generally on tender leaves . On an average , about 542 eggs are laid by one female. Incubation period is 4 days. Larval period lasts 13 to 15 days, the larva undergoing five instars. Durations of the different instars are 3 to 4 , 2 to 3, 2 to 3, 2 to 3 and 4 to 6 days respectively. The first instar caterpillars nibble and feed on the green matter on the undersurface at the base of the leaves and the later stage caterpillars web the leaves together and feed from inside skeletonising the leaves.
Morphological & Physiological studies on Helminthosporium halodes Drechs. The 'Leaf Rot' fungus of coconut
(Division of Plant Pathology, Agricultural College and Research Institute, Vellayani, 1963) Shanmughom, S N; Samraj, J
The strain of Helminthosporium halodes occuring in Kerala and causing leaf rot disease of the coconut palm was found to differ in certain respects from the type species and also from its known varieties. The dimmensions of the spores of this were far superior to that of others which were reported as H.halodes or as its varieties. The difference were very prominent in culture. Formation of secondary spores on definite secondary sporophores, proliferated from the primary spores occurs only in the coconut strain not in the type species or its varieties . The fungus is therefore considered as a new variety of H.halodes var nucifera var. nov.
Studies on the salt-affected rice soils of Kerala
(Division of Agricultural Chemistry, Agricultural College and Research Institute, Vellayani, 1963) Gopalakrishnan Nair, P; Subramoney, N
A pot culture study was conducted using different salts in different concentrations so as to produce varying conductivities in the soil. The influence of different concentrations of various salts on the growth and yield characteristics of rice were studied. Fourteen typical soil samples from the salt- affected areas in Kerala were also examined for their chemical and mechanical composition.
Investigations on the effect of foliar application of nitrogenous fertilizers on chewing tobacco (Nicotiana tabaccum Linn)
(Division of Agronomy, Agricultural College and Research Institute, Vellayani, 1963) Sukumaran, K M; Nair, C K N
Effect of date of sowing and combination of nitrogen, Phosphoric acid and potash on the growth and yield of sea island cotton ( Gossypium barbadense, Linn)
(Division of Agronomy, Agricultural College and Research Institute, Vellayani, 1963) Abdul Kalam, M; George, C M
Studies on Corynespora cassiicola (Berk. & curt) W E I.
(Division of Plant Pathology, Agricultural College & Research Institute, Vellayani, 1963) Gopalan, N; Sam Raj, J
Morphological and ecological studies on the lady bird beetle, Cheilotnenes sexmaculata Fabr. ( coccinellidae-coleoptera)
(Faculty of entomology, Regional post-graduate training centre, Agricultural college and research institute Coimbatore, 1963) Abraham Jacob
Studies on the influence of host and induced superparasitism on the pupal parasite Trichospilus pupivora Ferriere (Eulophidae)
(Division of Entomology, Agricultural College and Research Institute, Vellayani, 1963) Jayarathnam, K; Joseph, K V
The literature on the effect of host on parasites and that on Trichospilus pupivora has been reviewed. The total number of adults produced, sex ratio, developmental period, longevity and size of T. pupivora were accertained when bred on eight different speciesof host pupae, namely (1) Phytometra peponis (2) Prodenia litura, (3)Orthaga exvinacea, (4) Sylepta derogata, (5) Lampides boeticus, (6) Margaronia indica, (7) Nephantis serinopa, and (8) Gracillaria soyella. Correlation and regression studies show that there exist, a highly significant and positive linear correlation between the weight of the host pupa on the one hand and the number of parasites emerged, the proportion of females , the developmental period and the size of the parasites emerged, the proportion of females, the developmental period and the size of the parasites on the other. There does not appear to be any correlation between longevity of parasites and weight of host pupa.