INDIGENOUS CUCURBITS AND GRAFTING TECHNIQUES AFFECT CUCUMBER PRODUCTIVITY BY MODULATING MORPHO-PHYSIO-BIOCHEMICAL INDICES

Abstract

Vegetable grafting is a unique surgical horticultural technology for inducing soilborne biotic and abiotic stress tolerance in cucumbers. Indigenous cucurbit germplasm as rootstocks may show more tolerance potential compared to exotic ones. However, it needs evaluation for compatibility testing through various grafting techniques. Therefore, this study was planned to test available cucurbits as rootstocks for graft success vis-à-vis cucumber growth and productivity. It was carried out in the Plant Propagation and Physiology lab at MNS University of Agriculture, Multan, Pakistan. The seeds of the indigenous open-pollinated cucurbits were sown in 64-celled plug trays with peat moss as growing media, followed by shifting to 50-celled plug trays at the first true leaf emergence stage. The seeds of selected scion (cucumber) were sown after the emergence of rootstock seeds. Different grafting techniques were performed at the first true leaf stage of the scion, followed by healing and acclimatization. In this experiment, hybrid cucumber (cv Yalla F1) was grafted on three indigenous cucurbits, namely ridge gourd (Luffa acutangular), bottle gourd (Lagenaria sicearia) and pumpkin (Cucurbit pepo. L) for graft compatibility success by using three grafting techniques: cleft grafting, one cotyledon grafting and hole insertion. Non-grafted cucumber was grown to compare with grafted plants for growth and productivity. Overall, significant (p ≤ 0.5%) results were obtained regarding a 90% survival rate in cucumber plants grafted onto the bottle gourd through cleft grafting compared to the other grafting techniques. Additionally, the cucumber plants grafted on bottle gourd showed the highest morphological (root length, shoot length, root fresh weight, shoot fresh weight and rootstocks, and scion gir th), physiological (photosynthetic rate, transpiration rate, stomatal conductance, and sub-stomatal conductance), biochemical (antioxidants activities, SOD, CAT, and POX) and yield indices (average fruit length, weight, numbers, and yield) as compared to the non-grafted plants. Conclusively, cucumber grafting onto indigenous bottle gourd with cleft grafting technique exhibited maximum compatibility confirmed through physio-chemical attributes and improved plant biomass and yield, thereby suggested for cucumber grafting.