Maturity indices for harvesting of beans (Phaseolous vulgaris L.) variety Kentucky Wonder Green in dry zone cultivations in Sri Lanka.

Beans (Phaseolous vulgaris L.) are an economically important vegetable grown in nearly all parts of the world for fresh and processed markets. There are no locally developed maturity indices for the crop; therefore, this study was conducted to determine maturity indices for harvesting of bean variety Kentucky Wonder Green grown under dry zone conditions in Sri Lanka to ensure acceptable produce quality for local fresh produce and processing markets in Sri Lanka as well as potential export markets. Pods were harvested at four different maturity stages namely 9, 12, 15 and 18 days after fruit set (DAFS), and analysed for physico-chemical and physiological parameters such as pod weight, length, diameter, firmness, percentage seed weight, moisture, dry matter, fiber, total soluble solids (TSS), pH, titratable acidity, respiration and ethylene emission. They were also analysed for disease frequency (DF), visual quality rating (VQR), snapping quality (SQ) and weight loss under ambient storage. A sensory evaluation test was also conducted. The results revealed that commercial maturity of beans was achieved at 12 to 15 DAFS under dry zone conditions (temperature of 28±2 C and relative humidity of 69-78%) in Sri Lanka. For local fresh produce markets, pods can be harvested at their maximum length, before seeds become prominent. Objective indices such as weight to length ratio of ≤ 0.7, diameter of 1cm and firmness < 6 kg, percentage seed weight of 8–10%, pod weight to seed weight ratio of 7 and moisture content of 90% (w/b) can be used to determine the correct harvesting stage for potential export markets. Pods harvested at this stage can also be used for processing as they contained high TSS and dry matter. INTRODUCTION Beans (Phaseolous vulgaris), belong to the family Fabaceae and are popular vegetable crops grown in nearly all parts of the world. They are the major suppliers of vegetable proteins in developing countries as the pods and seeds are rich in protein and are also excellent sources of vitamins and minerals. 1 Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya. 2 Department of Food Science and Technology, Faculty of Applied Science, Sabaragamuwa University of Sri Lanka, Buththala, Sri Lanka.