​Standardization of Grafting in Bittergourd (Momordica charantia L.)

Abstract

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.

Effect of Different Physical and Chemical Treatments on Germination and Seedling Establishment in Spine gourd (Momordica dioica Roxb.)

“…This could be due to the beneficial effect of these chemicals in breaking seed dormancy. Similar results were also reported by Devi and Selvaraj [11] in bitter gourd and Panchbhai et al [12] in spine gourd. The external application of gibberellin interacts with growth inhibitors present in dormant spine gourd seeds lowering the inhibitors concentration and facilitating germination by breaking seed dormancy at an early date [13].…”

Seed Germination and Seedling Vigour of Spine Gourd (Momordica dioica Roxb.) in Response to Different Physical and Chemical Treatments

“…This is due to the beneficial effect of these chemicals in breaking seed dormancy. Similar results were also reported by Devi and Selvaraj [11] in bitter gourd, Vijayaraghavan [12] in Bhendi and Panchbhai et al, [13] in spine gourd. The antagonism between growth promoters and naturally occurring germination inhibitors plays an important role in seed dormancy and the external application of gibberellin interacts with growth inhibitors in dormant seeds lowering the inhibitors concentration and facilitating germination by breaking seed dormancy at an early date [14] and increasing germination.…”