Photoselective netting is well known for filtering the intercepted solar radiation, thus affecting light quality. While its effects on leaf mineral elements have been well investigated, how color netting affects fruit mineral nutrients remains elusive. This study was conducted to evaluate the effects of shade provided by blue and yellow nets on mineral nutrients of fig trees under rain-fed conditions. The experiment was arranged as a split-plot treatment in a randomized complete block design with three replications. Cultivars “Sabz” and “Siah” were covered with color nets or left uncovered (as the control group). The highest nitrogen content (8710 ppm) was recorded for cultivar “Sabz” covered with blue net. Color nets enhanced calcium concentration in cultivar “Siah”. Covering fig trees with yellow net increased magnesium content in cultivar “Siah” and phosphorus content in cultivar “Sabz”. Our observation showed the significant positive effect of photo selective nets on postharvest quality, by decreasing fig fruit weight loss and extending shelf life of fruits. In general, color nets as a new agro-technological approach can maintain fruit nutrition under rain-fed conditions and increase postharvest shelf life and quality of fresh fig.

No abstract

This study was carried out at the research field of Tarbiat Modares University, Peykan Shahr, Tehran to determine the changes in the content and chemical compositions of essential oil of tulsi (Ocimum. sanctum L.) at three different growth stages including vegetative, flower bud formation and full flowering stages. The essential oils of the aerial parts were extracted by hydrodistillation method using Clevenger apparatus, and analyzed by GC and GC-MS. The hydro-distillation of the aerial parts of Ocimum. sanctum at the vegetative, flower bud formation, and full flowering stages yielded 0.95%, 0.87% and 1.3% (w/w) EO, respectively. The main constituent of the EO from the vegetative stage were 1, 8-Cineole and β-bisabolen, while eugenol was found as the main compound of flower bud formation and full flowering developmental stages.

Covering fig trees with color nets changed the quality of light that reach trees. This study was carried out to assess the effects of shade provided by blue and yellow protection nets on leaf attributes and fruit quality of fig trees under rain-fed conditions. The experiment lasted for three months and was a split-plot treatment arrangement in a randomized complete block design with three replications. 'Sabz' and 'Siah' fig trees were covered with color nets or left uncovered (as the control group). The results showed that yellow nets reduced the net photosynthetic activity by 15.86 µmol CO 2 m −2 s −1 , but increased leaf chlorophyll and carotenoid content in both cultivars. Leaf temperature decreased in both cultivars when covered with yellow nets. The shade provided by blue nets increased stomatal conductance in the leaves of 'Sabz' fig trees. When covered with yellow shade nets, 'Sabz' fig trees had the highest relative water content and the lowest ion leakage in both cultivars. The color nets reduced dry fruit diameter in 'Sabz' figs and reduced total soluble solids in both cultivars. Also, titratable acidity decreased in fruits as a result of using yellow nets on both cultivars. Yellow nets increased antioxidant activity and anthocyanin content in fruits of the 'Siah' cultivar significantly, as compared with the 'Sabz' cultivar. The photoselective, light-dispersive shade nets proved to be interesting tools that can reduce drought stress on trees under rain-fed conditions.

No abstract