1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
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Item Etiology and management of bacterial wilt of yard long bean(Department of Plant Pathology, College of Agriculture, Vellayani, 2023) Talla Sushmitha; Sajeena AThe study entitled “Etiology and management of bacterial wilt of yard long bean” was conducted at College of Agriculture, Vellayani and Integrated Farming System Research Station (IFSRS), Karamana during 2020-2022 with an objective to identify and characterize the bacterium inciting wilt disease in yard long bean and management of the disease. Bacterial wilt infected yard long bean plant samples were collected from Vamanapuram (8.7226° N, 76.8971° E) and Nanniyode panchayat (8.6988° N, 77.0262° E) of Thiruvananthapuram district, Kerala. The disease incidence was 85 to 90 per cent. The disease symptoms included drooping and wilting of green leaves, collapse of stem followed by death of plants. The bacterium was isolated on triphenyl tetrazolium chloride (TZC/TTC) medium and three methods of pathogenicity tests viz., root dip, root dip and stem injection as well as soil inoculation were undertaken to prove Koch's postulates. The symptoms were observed within three to seven days after inoculation and complete wilting was observed in 7, 10 and 14 days in root dip, root dip and stem injection and soil inoculation respectively. Cultural studies revealed the bacterial colonies to be white or cream, circular, smooth, convex in casamino acid peptone glucose agar (CPG) and white, circular, smooth, convex, fluid like with pink colouration at centre in TZC medium which were the best media for the bacterial growth. Morphological and biochemical studies revealed the bacteria as gram negative, rod-shaped and facultative anaerobic. Molecular characterization using the universal primers of 16S rRNA viz., 27F/1492R revealed 99.83 per cent identity with several isolates of Enterobacter spp. and Kosakonia oryzae and the gene amplified using CM7F/CM31b primers of rpoB, one of four house-keeping genes of Enterobacteriaceae revealed 99.72 per cent identity with Kosakonia oryzae strain Ola51. The 16S rRNA and rpoB sequence were deposited in NCBI database (Acc. no. OP321041 and Acc. no. OP321041 respectively). Further, phylogenetic analysis and biochemical characterization using Enterobacteriaceae specific kit confirmed the pathogen to be K. oryzae. 142 In vitro evaluation of various chemicals by poisoned food technique and filter paper assay revealed that streptocycline (250 ppm) was the most effective bactericide resulting in a mean inhibition zone of 27.67 mm, followed by copper oxychloride 50 % WP (0.30 %) (17.00 mm) and copper hydroxide 77% WP (0.20 %) (15.33 mm). Among the various botanicals screened for antibacterial effect in vitro by paired plate technique, bulbs of Allium sativum revealed the highest inhibition of bacterial growth followed by leaves of Mansoa alliaceae. In agar well diffusion method, bulbs of A. sativum (15 %) followed by leaves of Boerhavia diffusa (20 %) and M. alliacea (20 %) resulted in maximum inhibition (inhibition zone of 20.33, 18.83, 16 mm respectively) of the bacterial growth. An in vivo study was undertaken at IFSRS, Karamana for the management of bacterial wilt disease in yard long bean (var. Geethika) using the best three treatments viz., bulbs of A. sativum (10g per pit), copper oxychloride 50% WP (0.30 %) and copper hydroxide 77 % WP (0.20 %) selected from in vitro studies along with streptocycline (250 ppm), bacteria inoculated and uninoculated treatments as checks. The inoculated control revealed 100 per cent disease incidence whereas soil application of crushed garlic bulbs (10 g/pot at one week before transplanting) followed by immediate covering with cow dung and soil mixture, seedling treatment and soil application of crushed garlic bulbs at 10, 20 and 30 days after transplanting (DAT) registered the minimum disease incidence (13.33 %) with the maximum number of pods (43), pod length (46.82 cm), pod weight (21.67 g) and pod yield (815.13 g) followed by soil application of copper oxychloride 50 % WP (0.3 %) (754.77 g pod yield) with 20 per cent disease incidence. Treatment application at 10, 20 and 30 DAT with 10 days interval (DI) was more effective than at 15, 30 and 45 DAT with 15 days interval. Biochemical studies on identifying the mechanism of disease toleItem Locating superior segregants with high yield and drought tolerance in yard long bean [Vigna unguiculata ssp. sesquipedalis (L.) Verdcourt](Department of Genetics and Plant Breeding, College of Agriculture, Vellayani, 2024-10-22) Noru Raja Sekhar Reddy; Beena ThomasYard long bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt), a member of Fabaceae, holds a significant position among legume vegetable crops. Climate change induced drought can significantly impact its cultivation, yield, and production. Among abiotic stresses, drought is severe and affects the quality of the pods, reducing their size and nutritional content, ultimately leading to decreased growth and yield. This study was entitled “Locating superior segregants with high yield and drought tolerance in yard long bean (Vigna unguiculata ssp. sesquipedalis (L.) Verdcourt)”. The study was conducted in Department of Genetics and Plant Breeding at College of Agriculture, Vellayani, from 2022 to 2024. The research comprised of three main experiments: evaluation of F2 segregants in the field, a laboratory analysis of screening of F3 seeds for drought stress tolerance using PEG, and evaluation of F3 segregants in the field. The previous Ph.D. research work entitled “Gene action and gene expression analysis in yard long bean (Vigna unguiculata ssp. sesquipedalis (L). Verdcourt) for drought tolerance” done in the Department of Genetics and Plant Breeding, College of Agriculture, Vellayani formed the materials of research work. The materials consisting of 200 seeds of yard long bean collected from F1 segregants from the cross of Katampally Local (Drought tolerant) ×Vellayani Jyothika (High yielding) were used for the present study. The collected 200 F2 segregants were evaluated for yield and various yield-related traits from September to December 2023. The seeds were sown at a spacing of 1.5 m х 0.45 m, and cultural operations were adopted as per the “Package of Practices Recommendations Crops 2016” of Kerala Agricultural University. From five superior segregants (F2-3, F2-79, F2-106, F2-130, and F2-184) the seeds were collected named as F3-1, F3-2, F3-3, F3-4, and F3-5. The collected seeds were used for laboratory experiment to assess drought tolerance by inducing osmotic stress in the laboratory. In the laboratory experiment, these five segregants were further assessed under drought stress conditions using two concentrations of PEG 6000 (-0.75 bar and -1 bar). Based 88 on germination percentage, root length, and seedling vigour index-I, F3-1 and F3-3 were identified as drought tolerant genotypes. The second field experiment (season - 2) involved the evaluation of the F3 segregants in a compact family block design with five progenies and five replications from February to May 2024. The seeds were sown at a spacing of 1.5 m х 0.45 m. The analysis of variance between families revealed that the mean sum of squares due to families was significantly different for all traits except pod width among all five families. The Bartlett’s test for homogeneity of error variances of five families indicated that error variances were homogenous for all characters except pod length, pods per plant, yield per plant, and crop duration. Genetic parameter analysis performed for five F3 families in traits like pod length, pod weight, pods per plant, yield per plant, and crop duration showed high phenotypic and genotypic variation, along with high heritability and genetic advance, indicating their suitability for selection. In the present investigation, the correlation studies indicated a significant positive correlation was shown by the characters like, pod weight, pods per plant, pod length, pod width, and harvest index with yield per plant. However, days to 50% flowering, crop duration, and vine length showed a significant negative correlation with yield per plant. Path analysis of the eight characters showing significant correlation with yield per plant revealed that the pod weight (1.09) and harvest index (1.03) exhibited a very high direct effect on yield per plant. The highest direct effect on yield per plant was shown by days to 50 % flowering (0.87) and pod width (0.79). A high indirect effect on yield per plant was shown by pod weight (3.32) through vine length. In conclusion, in field experiment (season-1) of evaluation of F2 segregants for yield and other related traits, genotypes F2-3, F2-79, F2-106, F2-130, and F2-184 were identified as superior for yield and other related traits out of 200 segregants. Genotypes F3-1 and F3-3 were identified as drought tolerant ones based on germination percentage, root length, and seedling vigour index-I in the laboratory experiment. In field experiment (season-2) of evaluation of F3 segregants for yield and other related traits, among five F3 families, F3-1 was identified as superior for yield and other related parameters. Within each family, superior progenies were progeny-1 (F3-1), progeny-1 89 (F3-2), progeny-2 (F3-3), progeny-3 (F3-4), and progeny-4 (F3-5). Based on the laboratory study, F3-1 was recognized as a superior segregant with drought tolerance. In field experiment, progenies from the F3-1 family showed high yield. These F3-1 segregants can be used in future breeding programmes for varietal development of yard long bean with high yield and drought tolerance.Item Nutrient profiling of yard long bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt) genotypes(Department of Vegetable Science, College of Agriculture ,Vellayani, 2023-03-25) Anitt Joseph; Sarada SThe project entitled "Nutrient profiling of yard long bean [Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt] genotypes" was carried out at the Department of Vegetable Science, College of Agriculture, Vellayani, during 2020–2022, to analyze the nutrient composition in green pods of yard long bean genotypes and to identify of the best genotype based on nutrient content. The experimental material consisted of 20 yard long bean genotypes, which was laid out in RBD with two replications. Analysis of variance revealed significant difference for all the characters studied among the twenty genotypes expect for sodium content. Among the genotypes, the highest pod length was observed for KAU Deepika (66.25 cm) and Kanjikuzhipayar (64.45 cm), FH-7 (63.60 cm) and NS- 621 (61.50 cm) being statistically on par with it. The highest pod girth was recorded in NS 621 (4.20 cm), which was on par with Supreme (3.80 cm) and Kanjikuzhipayar (3.80 cm). The highest pod weight of 33.60 g was recorded by FH 7, which was on par with Kanjikuzhipayar (32.45 g) and KAU Deepika (31.25 g). The highest number of pods per plant was recorded in Githika (47.00). VS 38 (46.00), Manjari (45.00), VS 54 (44.00) and KMV 1 (43.50) were on par with it. The highest yield per plant of 1087.15 g was recorded by Githika which was on par with KAU Deepika (1031.52 g). The highest moisture content of 89.77 % was recorded by NS 621 which was on par with FH 7 (89.53 %), Supreme (88.55 %), Kanjikuzhipayar (87.94 %), KAU Deepika (89.94 %) and Vellayani Jyothika (87.47 %). The lowest fat content was recorded in KAU Mithra (1.15 %) which was statistically on par with KAU Deepika (1.25 %), VS 16 (1.25 %), Supreme (1.35 %), Malika (1.40 %) and Lola (1.40 %). The lowest carbohydrate content was recorded in Lola (6.69 %) which was on par with VS 54 (7.05 %), Arka Mangala (7.15 %), Sharika (7.23 %), KMV 1 (7.27 %) and Harry (7.27 %). The highest ash content of 0.91 % was recorded in Vellayani Jyothika. The highest crude fibre content was observed in Lola (1.90 %) which was on par with VS 54 (1.90 %), Harry (1.86 %) and Vyjayanthi (1.85 %). The highest crude protein content was recorded by Arka Mangala (34.12 %). Kanjikuzhipayar (31.93 %), Manjari (31.81 %) and KAU Mithra (31.805 %) were found to be statistically on par with it. The highest beta carotene of 512.87 µg 100 g-1 was recorded in Vyjayanthi. The genotype KMV 1 recorded the highest vitamin B1 content of 0.94 mg 100 g-1 of dry weight. Githika (0.92 mg 100 g-1 of dry weight) and Lola (0.900 mg 100 g-1 of dry weight) were on par with it. The highest vitamin B2 and vitamin B3 content was recorded in Githika (0.40 mg 100 g-1 of dry weight and 2.21 mg 100 g-1 of dry weight respectively). Vitamin C content was the highest in Noori (26.28 mg 100 g-1 of fresh weight) which was statistically on par with Vyjayanthi (25.96 mg 100 g-1 of fresh weight), KAU Deepika (25.96 mg 100 g-1 of fresh weight), Githika (25.96 mg 100 g-1 of fresh weight), FH 7 (25.96 mg 100 g-1 of fresh weight) and Vellayani Jyothika (25.32 mg 100 g-1 of fresh weight). The highest potassium content of 1.83 % was recorded in Manjari. Two genotypes, viz., Kanjikuzhipayar (1.80 %) and Noori (1.75 %) were on par with it. Githika recorded the highest phosphorous content of 0.60 % which was on par with VS 38 (0.55 %). Vyjayanthi registered the highest magnesium content (0.63 %), which was on par with VS 16 (0.54 %), Githika (0.54 %), Manjari (0.48 %), VS 38 (0.48 %) and VS 54 (0.48 %). The highest iron content of 190.00 ppm was observed in VS 54, being on par with Lola (185.00 ppm). The highest zinc content was recorded in Manjari (82.50 ppm). FH 7 (77.50 ppm) and VS 54 (75.00 ppm) were found to be statistically on par with it. The lowest phytic acid content was recorded in Lola (825.63 mg 100 g 1).Vyjayanthi (832.69 mg 100 g-1), KAU Deepika (853.91 mg 100 g-1), Githika (853.94 mg 100 g-1), Sharika (853.94 mg 100 g-1) and NS 621 (859.24 mg 100 g-1) was found to be statistically on par with it.The lowest oxalate content was recorded in Supreme (2.20 mg g-1), which was statistically on par with Kanjikuzhipayar (2.25 mg g-1), Arka Mangala (2.30 mg g-1), Sharika (2.35 mg g-1) and KAU Deepika (2.70 mg g-1). The highest antioxidant content was recorded in Vellayani Jyothika (94.05 %). Arka Mangala recorded the highest mean score for colour/appearance and doneness. Highest mean score for flavour and taste was recorded in NS 621. The lowest bitterness was also recorded in NS 621. High phenotypic and genotypic coefficients of variation coupled with high heritability and high genetic advance was recorded for the characters pod length, pod weight, pods/plant, yield/plant, ash, vitamin B1, vitamin B2, Vitamin B3, potassium, phosphorous, iron and zinc. The genotypes were ranked based on selection index score considering the characters viz., carbohydrate, crude fibre, crude protein, beta carotene, vitamin B1, vitamin B2, vitamin B3, potassium, calcium, iron and antioxidant. Lola recorded the highest selection index score of 824.222 followed by Vyjayanthi (804.255) and VS 54 (789.976). The best genotype based on nutrient content was Lola, which recorded the highest crude fibre content, high vitamin B1 and iron content and the lowest carbohydrate and phytic acid content.Item Generation mean analysis in yard long bean (Vigna unguiculata subsp.sesquipedalis (L.) Verdcourt) for yield and mosaic resistance(Vegetable Science, College of Agriculture, Vellayani, 2024-02-13) Airina, C K.; KAU; Sarada, SThe present study ‘Generation mean analysis in yard long bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt) for yield and mosaic resistance ' was undertaken at the department of Vegetable Science, College of Agriculture, Vellayani, Thiruvananthapuram during 2017-2019 and at Pepper Research Station, Panniyur, Kannur during 2022-23 to develop high yielding and mosaic resistant yard long bean hybrids and to study the inheritance and gene action of yield and mosaic resistance using generation mean analysis. Seventy six cowpea genotypes were screened against the blackeye cowpea mosaic virus (BlCMV) to ascertain the disease reaction of the genotypes by artificial inoculation under pot culture method. Based on the extent of symptoms and vulnerability index (VI), three genotypes were found highly resistant, 11 genotypes showed resistant response, 13 genotypes were moderately resistant, 10 genotypes moderately susceptible, 20 genotypes susceptible and remaining 18 genotypes showed a highly susceptible reaction. The genotypes Manjari, VU-7 and EC-18734 were highly resistant to BlCMV. Five high yielding yard long bean genotypes viz; Vellayani Jyothika, Vyjayanthi, Geethika, KAU Deepika, and KAU Mithra which gave a susceptible response were selected as lines and three genotypes, viz. Manjari, VU-7 and EC-18734, which gave an immune response as testers for the development of 15 hybrids in a line x tester fashion. The hybrids and their eight parents were raised with a standard variety Lola and resistant check Manjari in a randomized block design with three replications in open field in Rabi 2022 and were tested for 19 yield characters and mosaic resistance. The mean squares due to parents were highly significant for all the characters, while for hybrids significant difference was observed for all the characters except pod girth and yield per plot. The PCV values for all the characters were found to be higher than the GCV values but in smaller magnitude, which implied a lesser influence of environmental factors for these characters. The PCV and GCV values ranged from 3.31 to 52.80 and 2.06 to 51.68, respectively. Heritability estimates expressed in percentage ranged from 26.00 % to 97.80 % and estimates of genetic advance ranged from 2.63 to 104. The genotypic correlation coefficients were higher in magnitude than that of phenotypic correlation coefficients for most of the traits under study, which clearly indicated the presence of inherent association among various characters. For yield per plant, significant positive correlation was estimated with vine length, pod length and pod weight, whereas significant negative correlation with branches per plant, days to first flowering and days to harvest. Significant GCA effects were recorded for all the characters except pod girth. Among the lines, KAU Deepika showed good general combining ability for days to first flowering, pod length, pod weight, 100 seed weight, yield per plant, yield per plot, days to harvest and keeping quality and among the testers, Manjari exhibited good GCA effect for vine length, pod length, pod weight, seeds per pod, pods per plant, yield per plant, yield per plot and keeping quality. Significant SCA effects were observed for 13 quantitative characters viz; vine length, primary branches per plant, terminal leaf length, terminal leaf width, lateral leaf length, lateral leaf width, days to first flowering, pod length, pod weight, 100 seed weight, and days to harvest, pod protein and keeping quality. Vyjayanthi x EC 18734, KAU Deepika x Manjari and KAU Mithra x Manjari were good specific combiners for pod weight and Vellayani Jyothika x EC 18734, Vyjayanthi x EC 18734, Githika x VU7 and KAU Deepika x Manjari for 100 seed weight. Desirable significant standard heterosis has been identified for 12 characters studied viz; no. of branches per plant, terminal leaf width, lateral leaf width, days to first flowering, days to harvest, pod weight, pods per plant, yield per plant, yield per plot, 100 seed weight, pod protein content and keeping quality. The crosses KAU Deepika x Manjari and KAU Mithra x Manjari registered significant positive heterosis over mid, better, and standard parents for pod yield and high mid-parent heterosis and standard heterosis for pods per plant. The highest magnitude of standard heterosis was identified for pods per plant (101.14 %), followed by yield per plant (75.30 %). Besides the heterotic potential, the hybrid KAU Mithra x Manjari, KAU Deepika x Manjari and Githika x Manjari were resistant to mosaic disease. In field evaluation during Rabi 2022, among the three testers, Manjari alone exhibited an immune response (VI-0.00) for mosaic disease. Other major pests and diseases observed in the field were pod borer, pod bug, fusarium wilt and anthracnose. The three crosses Githika x Manjari, KAU Deepika x Manjari and KAU Mithra x Manjari were selected and six generations i.e. P1, P2, F1, F2, BC1 and BC2 of each cross were evaluated under open field conditions to study the inheritance and gene action of mosaic resistance and yield parameters. For mosaic resistance, the scaling tests were non-significant which implied that additive-dominance model was adequate in Cross I and II, while dominance x dominance epistasis was prominent in cross III. Predominance of dominant gene action was noticed in cross II and III for yield per plant, while dominance x dominance (l) action in cross I. Duplicate type of epistasis was also observed in cross I and III for the trait. Epistatic interactions were observed for all the characters, except vine length and number of branches per plant in cross I (Githika x Manjari), additive x dominance being prominent in most of the traits. Predominance of dominant gene or dominance x dominance (l) interaction was noticed in majority of the traits in cross II ( KAU Deepika x Manjari). Significance of both additive x additive (i) component and dominance x dominance component or either one of the component was identified for the inheritance of yield traits in cross III (KAU Mithra x Manjari). Duplicate type of epistasis was revealed for eleven characters viz; vine length, terminal leaf length, lateral leaf length, days to flowering, pod girth, pod weight, hundred seed weight, yield per plant, crop duration, protein content and keeping quality, of which eight were present in cross II. The yard long bean hybrid KAU Deepika x Manjari, with good general combining ability for yield characters, high heterotic potential, high yield and mosaic resistance was identified as the best cross from the study.Item Characterization and management of powdery mildew of yard long bean (vigna unguiculata subsp.sesquipedalis (L.) verdc.) under protected cultivation(Department of Plant Pathology, College of Horticulture, Vellanikkara, 2018) Rahila Beevi, M H; Sainamole Kurian, PYard long bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdc.) is believed to be selected and developed from cowpea (Vigna unguiculata (L.) Walp.) for its long, succulent pods which are used as a vegetable. In Kerala, it is one of the most preferred vegetables having very high amount of protein, iron, calcium, vitamin A, Vitamin C and dietary fibre. It is considered as a remunerative crop under protected condition owing to its high market demand. However, incidence of diseases is a major setback hampering the production of yard long bean under protected conditions among which, powdery mildew is the most devastating one. In this background, the present study was undertaken to characterize the pathogen causing powdery mildew of yard long bean and to formulate a management strategy for the disease under protected cultivation. Purposive sampling surveys were conducted in seven locations of Thrissur district and the disease severity varied from 1.67 to 67.33 per cent. The results of the survey indicated that the severity of disease was more during pod bearing and harvesting stage. Since powdery mildews are obligate parasites, characterization was done based on the microscopic observation of pathogen present on the leaves. The fungi produced hyaline, branched and septate hyphae. The conidiophores were erect and cylindrical on which conidia were born in chains. Variability was observed regarding conidia and conidiophore characters of powdery mildew collected from different locations, based on which the isolates were grouped into two viz., PM 1 and PM 2. PM1 type was observed in all locations except Vellanikkara. Based on the morphological characteristics of conidia and conidiophores, it was identified as Erysiphe polygoni. PM 2 type obtained only from Vellanikkara in which conidia and conidiophore characters were similar to Podosphera sp. which is very rarely reported on legumes. Hence, its identity was further confirmed as Podosphaera xanthii by molecular characterization. The rRNA-ITS sequence was deposited in NCBI Genbank database with accession number MH645799. This is the first report of powdery mildew of yard log bean incited by Podosphaera xanthii. In-vitro evaluation of 17 treatments including fungicides, biocontrol agents and botanicals by spore germination technique revealed that all the treatments caused cent per cent inhibition of conidial germination. For taking forward eight promising treatments to the field experiments, they were tested in-vitro on detached leaves by artificial inoculation of conidia from infected leaves. Based on the per cent leaf area infected, two systemic fungicides, one contact fungicide, two biocontrol agents and one botanical were selected for field evaluation. Field experiments were conducted simultaneously inside polyhouse and rain shelter to evaluate the performance of selected fungicides, biocontrol agents and botanicals against powdery mildew. Among the treatments, low disease severity of 4.33 per cent and 7.67 per cent was recorded in T1- difenoconazole and T2 – tebuconazole respectively in polyhouse and these treatments were statistically on par. In rain shelter also, T1- difenoconazole and T2- tebuconazole recorded low disease severity of 7.67 per cent and 10.67 per cent respectively. The performance of wettable sulphur at lower and higher concentration did not differed significantly. All the four non-chemical treatments were equally effective in managing the disease both in polyhouse and rain shelter. Correlation analysis between the meteorological parameters and disease severity revealed that per cent disease severity was negatively correlated with temperature and relative humidity both in polyhouse and rain shelter. Analysis of population of phylloplane microflora showed that, there was a drastic reduction in the population of phylloplane fungi and bacteria after spraying chemical fungicides which is an indication of the toxicity and non-selectivity of these chemicals. Survival ability of biocontrol agents sprayed on the leaves were studied and found out that both Trichodema viride and Pseudomonas fluorescens survived on the leaves for seven days. Residue analysis of difenoconazole, the most effective chemical fungicide revealed that the compound with initial deposition of 0.21 mg kg-1 dissipated to 0.09 mg kg-1 after seven days in polyhouse whereas, the residue after seven days in rain shelter was 0.19 mg kg-1. The faster degradation of the chemical inside polyhouse may be attributed to the higher temperature prevailed during the experiment. Evaluating the results various experiments in the present investigation, it was found that, even though chemical fungicides provided best disease control, considering their toxic effect on beneficial non target microflora on the phylloplane and the residue left on edible pods, biocontrl agents such as Trichoderma viride and Pseudomonas fluorescens which exhibited consistent performance with moderate disease control and sufficient survival on the leaf surface would be ideal to control powdery mildew of yard long bean if applied at right time. Moreover, frequent application of systemic fungicides with single site action can result in the development of resistant strains of pathogens. So such chemicals should be adopted only if the disease severity is very high and cannot be managed with biocontrol agents.Item Soil and nutrient management for supperssion of fusarium wilt disease of yard long bean (vigna unguiculata subsp. sesquipedalis (L.) verdcourt)(Department of Soil Science & Agricultural Chemistry, College of Agriculture, Vellayani, 2018) Sooraj, R S; Biju JosephItem Generation mean analysis in yard long bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt) for yield and quality(Department of Vegetable Science, College of Agriculture, Vellayani, 2018) Merin Elza George; Sarada, SItem Bio-ecology and management of borer pests infesting yard lond bean, Vigna unguiculata subsp. sesquipedalis (L.) verdc.(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2018) Sontakke Pritin Pramod; Amritha, V SItem Crop weather relationship of yard long bean (Vigna unguiculata subsp. sesquipedalis(L.) walp)(Department of Agricultural Meteorology Vellanikkara, 2016) Aswini Haridasan; Ajithkumar, B