ASHOKA RANI, YASIF KHAN, MOHAMMAD2018-05-072018-05-072016http://krishikosh.egranth.ac.in/handle/1/5810044741D5259A field experiment was carried out at Agricultural College Farm, Bapatla during kharif 2015 to study the effect of calcium and boron nutrition on tolerance of blackgram (Vigna mungo.) to Yellow Mosaic Virus. The experiment was laid out in split plot design with two main plot treatments viz., resistant cultivar PU-31 (M1) and susceptible cultivar LBG-623 (M2) and sixteen subplot treatments (S1 : Control ; S2:100 kg gypsum ha-1 ; S3: 200 kg gypsum ha-1; S4: 300 kg gypsum ha-1; S5:1 kg boron ha-1 S6: 2 kg boron ha-1; S7: 3 kg boron ha-1; S8: 100 kg gypsum + 1kg boron ha-1; S9: 100 kg gypsum + 2 kg boron ha-1; S10: 100 kg gypsum + 3 kg boron ha-1;S11: 200 kg gypsum + 1 kg boron ha-1; S12: 200 kg gypsum + 2 kg boron ha-1; S13: 200 kg gypsum + 3 kg boron ha-1; S14: 300 kg gypsum + 1 kg boron ha-1;S15: 300 kg gypsum + 2 kg boron ha-1; S16: 300 kg gypsum + 3 kg boron ha-1) in three replications. Gypsum and boron were applied to soil as basal. The findings of the experiment revealed significant differences between varieties and treatments. The observations recorded such as disease incidence, whitefly count, plant height, number of branches, leaf area, total dry matter and its partitioning, measured at different intervals and yield components and yield were significantly affected by gypsum, boron and gypsum + boron application. The reduction in disease incidence with varied application of gypsum and boron ranged from 1.6 to 3.2 % at 30 DAS, 7.1 to 11.7% at 45 DAS and at later stages the effect was nonsignificant. The reduction in disease incidence was high with S14 treatment. In LBG-623, the reduction in disease incidence with gypsum , boron and gypsum + boron application was 3.3 to 24% at 30 and 45 DAS and at later stages the effect was nonsignificant. The maximum reduction was obtained with 300 kg gypsum + 1 kg boron ha-1 followed by 300 kg gypsum + 2 kg boron ha-1. The incidence of whitefly was less in PU-31 (62.7% at 15 DAS, 51.8% at 30 DAS,47.3% at 45 DAS and 36.9% at 60 DAS ) than in LBG-623. The percent reduction in whitefly population with application of gypsum, boron and gypsum + boron at different levels ranged from 8.0 to 84.9, 13.4 to 56.8, 11.7 to 58.3 and 19.8to 86.2 at 15,30,45 and 60 DAS respectively. In LBG-623, the percent decrease in whitefly population with gypsum application was 6.0 to 56.5,6.0 to 41.6,12.4 to 39.3 and 19.9 to 59.8% at 15,30,45 and 60 DAS respectively. Boron application reduced the whitefly incidence by 30.2 to 40.2,19.4 to 32.7,18.3 to 28.0 and 41.9 to 50.8% at 15,30,45 and 60DAS respectively. Gypsum + boron application reduced it by 32.3 to 84.6, 29.8 to 53.5,29.6 to 47.8 and 48.5 to 88.4% at 15,30,45 and 60 DAS respectively, the highest reduction was associated with 300 kg gypsum + 1 kg boron ha-1. LBG-623 grew taller than PU-31. Gypsum , boron , gypsum + boron application did not influence the plant height upto 45 DAS. At 60 DAS, the increase in plant height was 4.1,4.7,7.0,9.3 and 5.4 cm with S3,S10,S14,S15 and S16, respectively over control. Gypsum, boron and gypsum + boron application increased the number of branches by 6.5 to 16.1, 8.1 to 11.3 and 12.9 to 25.8 percent respectively and the highest increase was associated 300 kg gypsum + 1 kg boron ha-1 followed by 300 kg gypsum + 2 kg boron ha-1. Upto 45 DAS, there was no considerable variation in leaf area between varieties. At 60 DAS, the leaf area of LBG-623 was 1.6 folds higher than PU-31. The enhancement of leaf area with 200 kg gypsum ha-1 was 1.2 folds, with 2 kg boron ha-1, 3 kg boron ha-1, it was 1.11 folds and with gypsum + boron it was 1.1 to 1.3 folds higher than control. The maximum increase was associated with the treatment 300 kg gypsum + 1 kg boron ha-1. Accumulation of drymatter in leaf was 32.7 percent higher in LBG-623 than in PU-31. Gypsum, boron and gypsum + boron nutrition increased the drymatter accumulation in leaf by 23.8 to 28.7, 27.9 to 45.9 and 16.0 to 67.6% respectively over control, the paramount increase was obtained with S11 and S14. In LBG-623, increase in leaf dry matter with gypsum and boron application was 6.8 to 82.9 percent over control, the highest with 200 kg gypsum + 1kg boron ha-1. The accumulation of drymatter in stem was 35.4% greater in LBG-623 than in PU-31. Gypsum, boron and gypsum + boron application resulted in 11.9 to 63.3,24.8 to 29.4 and 32.1 to 86.2% increase in stem drymatter respectively over control, the highest with 300 kg gypsum + 1kg boron ha-1. In LBG-623, it was increased by 18.3 to 77.5, 27.5 to 30.0 and 31.7 to 103.3% respectively , the highest with 300 kg gypsum + 1 kg boron ha-1. Pod drymatter in PU-31 and LBG-623 on par. Gypsum, boron and gypsum + boron at varied levels increased the pod drymatter by 36.9, 12.3 to 21.5 and 24.6 to 44.6% respectively over control, the maximum increase was obtained with S14 treatment. Total drymatter production was observed more in LBG-623 than in PU-31. Application of gypsum alone at different levels increased the total drymatter production by 9.1 to 44%. Boron alone increased it by 19.4 to 24.2% and the combined application resulted in 20.5 to 62.5% increase in total drymatter production. Even though interaction effects were nonsignificant, in YMV infected LBG-623, 300 kg gypsum +1 kg boron ha-1 increased the total drymatter production by 56.5%. Pu-31 possessed more number of pods plant-1( 36.1%) than LBG-623. Combined application of gypsum and boron increased the pod number plant-1 over control by 10.3 to 50.0%. In Pu-31, 11.3 to 58.6% and in LBG-623, 20.2 to 38.4% increase was obtained with gypsum + boron nutrition. 100 seed weight and pod weight plant-1 increased by 33.3 to 44.4% and 24.6 to 44.6% respectively. Seed yield obtained in PU-31 was 2.4 folds higher than in LBG-623. 1.2 to 1.7, 1.3 to 1.4 and 1.4 to 2.1 folds improvement in seed yield was obtained with gypsum, boron and gypsum + boron, respectively. In YMV susceptible cultivar LBG-623, gypsum addition improved the yield by 2.3 folds, boron by 1.6 to 1.7 folds and gypsum + boron by 1.8 to 2.9 folds over control, the highest was obtained with 300 kg gypsum + 1 kg boron ha-1 followed by 300 kg gypsum + 2 kg boron ha-1. Total phenols were found higher in LBG-623 than in PU-31. The increase in content of total phenols was higher with gypsum + boron both in healthy (26.8 to 51.8% at 15DAS, 50.0 to 82.0% at 45DAS) and diseased leaves (32.5 to 53.2% at 45 DAS). Peroxidase activity in healthy leaves (41.2 and 33.3% at 15 and 45 DAS respectively) was found higher in LBG-623 than in PU-31. In diseased leaves at 45 DAS, it was 17.1% higher in PU-31 than in LBG-623. Among the treatments, peroxidase activity in both healthy (1.5 to 2.4 and 1.4 to 2.3 times at 15 and 45 DAS, respectively) and diseased (1.2 to 1.6 times) leaves was higher in combined application, the highest was found in S14. In healthy leaves of LBG-623, 1.7 to 3.5 (15DAS), 1.5 to 2.9 (45DAS) times and in diseased leaves 1.1 to 1.3 times increase in Peroxidase was observed, the maximum with S14.. Phenylalanine ammonia lyase activity was found higher in LBG-623 than in PU- 31. At 15 DAS and 45 DAS the maximum was obtained in S14 .In susceptible cultivar the maximum was obtained with 300 kg gypsum + 1 kg boron ha-1 at both 15 and 45 DAS. Phenylalanine ammonia lyase activity was found higher (10.1 & 8.3% in healthy leaves at 15 and 45 DAS respectively; 4.8% in diseased leaves) in LBG-623 than in PU-31. With gypsum + boron nutrition, the increase in Phenylalanine ammonia lyase activity in healthy leaves was 16.7 to 46.7 % at 15 DAS, the maximum was obtained with S14 and 39.7 to 65.1% at 45 DAS, the maximum was obtained with S14 followed by S15 . In diseased leaves, it was 17.2 to 28.3%. The extent of increase in Phenylalanine ammonia lyase activity with gypsum and boron nutrition was more in resistant cultivar than in susceptible at 15 DAS i.e., before the incidence of YMV. After the incidence of YMV, the extent of increase in Phenylalanine ammonia lyase activity in healthy leaves was more in susceptible cultivar than in resistant one. In susceptible cultivar, gypsum + boron nutrition increased it by 7.5 to 40.3% at 15DAS and 54.8 to 72.6 % at 45 DAS, V2S14 recorded the maximum increase at both the days. Leaf epicuticular wax content prior to disease incidence was 9.1% higher in PU- 31 than in LBG-623. After the incidence of YMV, at an age of 45DAS, it was higher in LBG-623 (13.5 & 3.9% in healthy and diseased leaves respectively). The increase in wax content was higher with gypsum + boron application than the individual application and it was 1.8 to 2.5 and 1.6 to 2.4 folds in healthy leaves at 15 & 45 DAS respectively and 1.4 to 2.0 folds in diseased leaves. In LBG-623, wax content was 1.5 to 2.3 and 1.4 to 2.0 folds in healthy leaves at 15 to 45DAS respectively and 1.4 to 2.2 folds in diseased leaves, the higher value for both healthy and diseased leaves was obtained with V1S14 . Calcium concentration in leaf of PU-31 was slightly higher than LBG-623 (1.4% at 15 DAS 1.0% at 30 DAS). Later (45 & 60 DAS) , compared to LBG-623, PU-31 had 3.6 and 5.3 % higher Ca in healthy leaves. The concentration of Ca in diseased leaves of LBG-623 was 3.5% higher at 45 DAS and 3.4% higher at 60 DAS than in PU-31. With gypsum and boron nutrition, enhancement in Ca level was more in susceptible cultivar than in resistant. In LBG-623, combined application enhanced the Ca level at 15DAS by 1.4 to 1.5 folds, the maximum with V2S9 to V2S16 and V2S3. At 30 DAS, it was 1.3 to 1.4 folds, the maximum increase was attained with V2S10 followed by V2S12 and V2S16. At 45 DAS in healthy leaves it was 1.2 to 1.3 folds, the maximum was observed with V2S16 followed by other combinations of gypsum+ boron (except V2S8 ) and V2S3. In diseased leaves, it was 1.4 to 1.6 folds, the maximum increase was attained with V2S14 followed by V2S15 over control. K content in leaf of LBG-623 was 11.4 and 23.7 % higher than PU-31 at 15 and 30 DAS respectively. Later (45 DAS ) LBG-623 possessed 13.1% lesser K in healthy leaves and 43.5 % higher K in diseased leaves. At 60 DAS , LBG-623 had 39.4 and 3.9% higher K in healthy and diseased leaves respectively. In LBG-623, combined application of gypsum and boron enhanced the K content at 15 DAS by 1.2 to 2.6 folds, the paramount increase was obtained with V2S14. At 30 DAS it was 1.4 to 2.4 folds , the paramount increase was obtained with V2S4 followed by V2S5. With the treatment 300 kg gypsum + 1kg boron ha-1, leaf K content in LBG-623 at 30 DAS reduced by 16% compared to that at 15 DAS. At 45 DAS, in healthy leaves it was 1.2 to 1.8 folds and in diseased leaves 1.8 to 2.7 folds, the paramount increase was obtained with V2S14 . LBG-623 had 50.0 & 20.2 % higher boron content in leaves than PU-31 at 15 and 30 DAS respectively. Later (45 & 60 DAS) compared to PU-31, LBG-623 had 4.1 and 5.5 % high B in healthy leaves and 26.4 and 32.7% high B in diseased leaves respectively. The concentration of boron in diseased leaves of LBG-623 was 1.5 folds higher than in healthy leaves. In diseased leaves of PU-31, it was 1.2 folds higher than in healthy leaves. In LBG-623, gypsum +boron application increased the boron content at 15 DAS by 1.2 to 1.5 folds, the maximum was obtained with 200kg gypsum + 3 kg boron ha-1 ( V2S13 ) which was on par with the treatments V2S14 to V1S16. At 30 DAS it was 1.7 to 2.3 folds, the maximum was obtained with 300 kg gypsum + 3 kg boron ha-1 ( V2S16 ) which was on par with V2S14 and V1S15. From these finding investigations, it can be concluded that application of 300 kg calcium + 1kg boron ha-1 along with vector control measures reduce the disease severity and improves the growth and yield in blackgram.en-USnullThesis