Changes in postharvest quality of guava affected by preharvest application of crop regulators.
Singh, B. P.; Singh, G.; Singh, A. K.;
Singapore Journal of Primary Industries Year: 1996 Vol: 24 Pages: 1-9 Ref: 16 ref.
1996
บทคัดย่อ
In studies carried out at Lucknow, India, during 1990-93, urea (10%, 15% and 20%), ethephon (1800 ppm), potassium iodide, (5000 ppm) or NAA (600 ppm), were applied twice at 10-day-intervals during flowering to cv. Sardar guava trees using 0.1% Triton X-100 (polyethylene glycol 4-tert-octylphenol ether) as the surfactant; controls were sprayed with water. Green-mature, winter guava fruits having a specific gravity of <1.00 were hand picked, washed, air dried and packed in wooden crates using newspaper as a lining material and stored under ambient conditions (18 plus or minus 2 deg C, 40-50% RH). Various storage attributes were observed on the 4, 6 and 8th days of storage. Maximum yield during the winter season was recorded from trees treated with 600 ppm NAA, followed by 1800 ppm ethephon and 20% urea. Among the various treatments, KI at 5000 ppm was the best for ripening as indicated by higher yellowness index, better appearance, firmness and organoleptic quality, and reduced weight loss during
storage; quality in terms of total soluble solids and vitamin C [ascorbic acid] contents was also best with this treatment. The fruits of trees given 20% urea or 1800 ppm ethephon deteriorated rapidly as observed by skin browning which gave an unattractive appearance, over-ripe taste, and desiccation of skin tissues resulting in poor quality and marketability of the fruits. It is concluded that KI at 5000 ppm could be used successfully to regulate the rainy season crop, and enhance winter yields and postharvest qualities of winter season crops.