Hossein Astaraki; Hossein Ramshini; Mahmoud Lotfi; Ali Izadi Darbandi
Abstract
Development of cultivars with high yield under normal conditions and maintaining their yield under abiotic stresses is the main purpose of plant breeding programs in arid and semi-arid areas. The present study aimed to evaluate the yield stability of a collection of commercial melon varieties under drought ...
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Development of cultivars with high yield under normal conditions and maintaining their yield under abiotic stresses is the main purpose of plant breeding programs in arid and semi-arid areas. The present study aimed to evaluate the yield stability of a collection of commercial melon varieties under drought stress. The trial was conducted in a field under normal conditions (plants were irrigated after 50 mm evaporation of a class A evaporation pan) and drought stress conditions (irrigation was carried out after 100 mm evaporation of a class A evaporation pan). In average, 3.32 kg fruit/plant and 2.76 kg fruit/plant were obtained under normal and drought stress conditions, respectively. The highest reduction in yield as the consequence of drought exposure was recorded for 'Mazandarani' (52%) and 'Samsoori' (48%). The most drought-tolerant genotypes were 'Mamaghani', 'Nahavandi', 'Shadegan', 'Crenshaw' and 'Suski-e-Sabz' as they had constant yield under both growing conditions. On the other hand, 'Samsoori' and 'Saveh' were the most sensitive genotypes to drought. For most of the measured traits, the values of broad-sense heritability were over 0.50 i.e. there was a large genetic diversity among melon genotypes. This variation can be utilized for selecting high potential fruit yield and drought-tolerant genotypes. Total soluble solids (TSS) (ºBrix) was 15.2% for 'Honey-Dew'. TSS (ºBrix) was obtained 10.7, 10.09, and 9.2% for Iranian genotypes of 'Khatooni', 'Samsoori', and 'Saveh', respectively. In conclusion, although some Iranian melon genotypes were recognized as drought tolerant, they need to be improved for TSS (ºBrix).
Taher Barzegar; Pouria Moradi; Jaefar Nikbakht; Zahra Ghahremani
Abstract
To investigate effects of putrescine (Put) and humic acid (HA) on fruit yield and physiological attributes of okra (Abelmoschus esculentus L. 'Kano') under water deficit stress, a field experiment was conducted in split plot based on a randomized complete block design with three replications. Plants ...
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To investigate effects of putrescine (Put) and humic acid (HA) on fruit yield and physiological attributes of okra (Abelmoschus esculentus L. 'Kano') under water deficit stress, a field experiment was conducted in split plot based on a randomized complete block design with three replications. Plants were exposed to three different irrigation regimes (33%, 66% and 100% ETc) and were treated with foliar application of Put (0, 0.5, 1 and 1.5 mM) and HA (0, 150 and 300 mg l-1). The results showed that deficit irrigation significantly decreased fruit yield, relative water content (RWC), vitamin C and water use efficiency (WUE), whereas proline content and catalase and peroxidase activities were increased. Foliar application of HA and Put significantly increased fruit yield, RWC, vitamin C and proline contents, catalase and peroxidase activities and WUE. The results suggested that HA at 300 mg l-1 and Put at 1.5 mM can improve growth, yield and quality of okra fruits.
