جستجوی مقالات مرتبط با کلیدواژه "supplemental irrigation" در نشریات گروه "منابع طبیعی"

Fig trees are the most common type of rainfed orchards in Fars province. In droughts, due to rainfall decline, the trees water requirement is not met and supplementary irrigation is necessary. Thereby, to reduce the damage caused by drought stress on fig (Sabz cultivar) under rainfed conditions, the present study was carried out to evaluate the effect of different levels of water stress on quantitative and qualitative characteristics. Experiment was conducted in a randomized complete block design with four replications (one tree per each replication) in Estahban fig research station. The treatments comprised of different water stress index (WSI), 0.0 (no water stress), 0.2, 0.4, 0.6, 0.8 and without supplementary irrigation. WSI was determined by recording leaf temperature, environmental humidity and air temperature and its effect on figs characteristics was measured. Results showed that the 0.4 WSI had the lowest leafy chlorosis disorder (1.4%) with one-time supplementary irrigation annually (1.5 m3 water per tree for each supplementary irrigation), but the difference was not significant with the 0.0 WSI (6 times supplementary irrigation equal to 9 m3 water per tree annually). The value of leaf relative water content in the 0.4 WSI was 53.4%. The 0.4 WSI showed the highest content of chlorophyll, carotenoid, syconium number per shoot and high quality (open ostiole) of dried fruit with the values of 0.05, 3.25 mg. g-1, 3.2 and 3.6%, respectively however the differences were not significant with the 0.0 WSI. In general, the 0.4 WSI was recommended for Sabz cultivar fig to maintain tree health, production of acceptable quality fruits, save groundwater, and sustainable agriculture.

In order to investigate the effect of supplemental irrigations (at flowering, podding, flowering + podding and rainfed as check) and exogenous application of different growth hormones (3 indoleacetic acid [IAA], gibberellic acid [GA3], 6 benzylaminopurine [6 BAP] and distilled water as check), an experiment was conducted at Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran. The results showed that the interaction of supplemental irrigation and hormone was significant on green pod yield, biological yield, 100-grains weight, harvest index. The number of pods per plant and grains per pod were influenced by the effects of supplemental irrigation and hormones. The use of supplemental irrigation at two stages (flowering and podding) and the application of hormones (IAA and 6-BAP) led to produce the highest grain yield, biological yield and 100-grains weight. Exogenous application of 6-BAP increased the Fv/Fm (photochemical efficiency of photosystem II), performance index, soluble sugar, soluble protein and leaf relative water content. In general, the supplemental irrigation and exogenous application of growth hormones particularly IAA and 6-BAP, can be suitable to prevent exposure of pea to drought stress during critical stages of flowering and podding and thus increases its economic performance.