The Potential of New Purple Yardlong Bean Varieties in Open-Field Organic Farming Compared with Chemicals Management under Plastic Net-House

Abstract

The purple yardlong bean "Muang Rachamongkol" is a pure line variety and was improved under organic farming. To examine this variety potential, a randomized complete block design was planned with 4 replications of 20 plants each, in comparison with two varieties: “Sirindhorn#1” and “Laisua Jakkaparn”. These bean varieties were grown during September-November 2020 under 2 production systems; 1) organic system under open-field and 2) under plastic net-house. The results showed that the characteristics of the new variety such as flower, fruit, and seed characters differed from the comparative varieties. For plant growth including plant height and the number of branches, and the interaction between the production system and varieties during the 3rd-6th weeks after planting were found to be significantly different. Plants grown under a chemical system showed a higher plant height and number of branches than an organic system, and varieties “Muang Rachamongkol” and “Sirindhorn#1” showed the highest plant height in both conditions. In addition, the influence of the production system was observed with the chemical system which showed the high number of pods, total pod yield, and pod weight of 34.91 pod/plant, 815.11 g/plant, and 27.67 g/pod, respectively. “Muang Rachamongkol” showed 27.15 pod/plant, 611.83 g/plant, and 26.41 g/pod, which was similar to the responses of “Sirindhorn#1” for the growth, yield, uniformity score, and plant vigor score in both of organic and chemical conditions.