Showing papers by "Raphael A. Stern published in 2000"
TL;DR: In this article, the authors investigated the interaction between irrigation and crop load in their effect on fruit size distribution in a "Spadona" (Pyrus communis) pear orchard located in a semi-arid zone.
Abstract: SummaryThe interaction between irrigation and crop load in their effect on fruit size distribution was investigated in a ‘Spadona’ (Pyrus communis) pear orchard located in a semi-arid zone. Five crop coefficient treatments were applied during the main fruit expansion phase: 0.25 KC, 0.40 KC, 0.60 KC, 0.80 KC, 1.00 KC where the crop coefficient (KC) is the applied irrigation level divided by the USDA "Class A" pan evaporation rate. An additional irrigation treatment (0.80 KC-ED) studied the effect of early water deficit. Crop load was adjusted to 200 to 800 fruits per tree in the 900 trees per ha orchard, by hand thinning. Cumulative irrigation levels up to harvest were 271, 351, 465, 572, 502 and 688 mm, in the 0.25 KC, 0.40 KC, 0.60 KC, 0.80 Kc, 0.80 KC-ED and 1.00 KC treatments, respectively. Crop yield increased with irrigation rate and crop load, with no interactions between the two. Total yields of fruits larger than 55, 60 and 65 mm increased with increasing irrigation level up to crop coefficient o...
24 citations
TL;DR: Application of TP as Tipimon or TPA as Maxim at the young fruitlet stage significantly increased yield in three lychee cultivars and TPA increased fruit size and weight, relative to both controls and TP-treated trees.
Abstract: Additional index words, abscission, auxin, truitlet, Litcht chinensis Application of TP as Tipimon® or TPA as Maxim®at the young fruitlet stage significantly increased yield in three lychee (Litchi chinensis Sonn.) cultivars: Mauritius', 'Floridian', and 'Kaimana'. Application of TP followed by TPA a week later increased yield more than did either substance alone. In all experiments, TPA increased fruit size and weight, relative to both controls and TP-treated trees. The increased yield did not prevent the increase in fruit size. Use of sprays of TPA may be an effective way of satisfying the market demand for large lychee fruit. Chemical names used: 2,4,5-trichlorophenoxypropionic acid (TP); 3,5,6-trichloro-2-pyridyloxyacetic acid (TPA).
22 citations
TL;DR: During the last six years, it has been studied the effect of putrescine, applied at the beginning of female bloom, on ‘Mauritius’ fruit yield, and a significant yield increase, of about 50%, was obtained with all treatments.
Abstract: SummaryDuring the last six years, we have studied the effect of putrescine, applied at the beginning of female bloom, on ‘Mauritius’ fruit yield. Concentrations required varied from year to year, but consistent increases were obtained with 5.10‒5,2.5.10‒4 and 5.10‒4 M putrescine. In 1994, inflorescences were immersed in a putrescine dichloride (putrescine) solution at 5.10‒6, 5.10‒5,5.10‒4, or 5.10"3 M. The two intermediate concentrations significantly increased the number of fruits per panicle, by about 100%. In 1995, individual trees were sprayed with putrescine at 1.10‒5, 5.10‒5, 2.5.10‒4, 5.10"4, or 5.10‒3 M. The best effect was obtained at the three intermediate concentrations. In 1996, individual trees were sprayed with putrescine at 5.10‒5, 2.5.10‒4, or 5.10‒4 M (8, 40 or 80 ppm, respectively). A significant yield increase, of about 50%, was obtained with all treatments. In 1997 and 1998, large-scale trials were conducted, using 40 ppm putrescine. In 1997, yield was increased by 102%, from 4.1 to 8...
16 citations