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Background: Papaya (Carica papaya L.) belonging to Caricaceae family has long been recognized as a wonder fruit of the tropics and grown predominantly for its delicious taste and extraction of its digestive constituent papain. As vegetative growth and flowering is simultaneous in this crop, supply of requisite amount of nutrients is necessary during the active growth period, which is possible through fertigation. Knowledge on correct dose of fertilizers to be provided through fertigation is very crucial. Methods: A field experiment was conducted during the period 2018-2020 at Instructional Farm, College of Agriculture, Vellayani, Thiruvananthapuram to investigate the response of fertigation and foliar spray on yield and fruit quality of papaya variety Surya. The experiment was laid out in randomised block design with combination of four fertigation doses of 75%, 100%, 125% and 150% RDF of N and K and three foliar sprays (1% 19:19:19, 0.5% ZnSO4+0.3% borax and water spray) which where compared with soil application of recommended dose of NPK (control 1) and soil application of NPK plant-1 year-1 based on soil test data as organic manures as combination of FYM, poultry manure and vermicompost in the ratio of 2:1:1 (control 2). Result: The findings of the study revealed that application of 100% RD of N and K through fertigation at weekly interval from one MAP to 20 MAP and foliar sprays of 0.5% ZnSO4 and 0.3% borax at 4th, 8th, 12th and 16th MAP (T5) along with basal application of 850 g rock phosphate and 15 kg FYM improved the yield and fruit quality parameters and can be recommended for commercial papaya cultivation.

Background: Commercial cultivation of bitter gourd is affected by biotic stresses like mosaic disease, fusarium wilt and root-knot nematode as well as abiotic stress like drought. Grafting with resistant rootstocks can be a tool to control these problems. In vegetable production, grafting is exploited commercially in many parts of the world. The cultivated area of grafted solanaceae and cucubitaceae plants has increased tremendously in recent years because of the advantages of grafted plants. Commercial use of vegetable grafting is a relatively recent innovation in India and scientific information on grafting in bittergourd is meager. In this context, identification of suitable rootstocks and standardization of grafting techniques that do not have adverse effect on yield and fruit quality not only lay foundation for further evaluation on tolerance to different biotic and abiotic stresses but also enhance the area and production of bitter gourd especially in sustainable production systems. Methods: Grafting in bitter gourd was carried out with three grafting methods such as hole insertion grafting, one cotyledon grafting and cleft grafting using growth regulators viz., alar and CCC to control height of rootstocks in order to identify suitable method, growth regulator and its concentration. The grafting experiment was done independently to four cucurbitaceous rootstocks viz., sponge gourd, pumpkin, bottle gourd and bitter gourd using bittergourd var. Preethi as scion. Height and diameter of the rootstocks before grafting were recorded and then the growth regulators alar and CCC each at 10 mgL-1 and 50 mgL-1 along with distilled water as control were sprayed on rootstocks in order to prevent the lodging of the root stocks and then grafted using different methods. Days taken for graft union and percentage success were also evaluated after grafting. Result: Our study of grafting bitter gourd scion into four cucurbitaceous rootstocks utilizing three methods and two growth regulators at two different concentration along with control exhibited significant difference in graft success among the methods as well as concentration of growth regulator in all four experiments. This work can be further utilized for imparting resistance against abiotic and biotic stresses in bitter gourd by selecting suitable rootstocks.