No abstract

The citrus leafminer (Phyllocnistis citrella Stainton) is a significant pest for Citrus spp. worldwide. Hence, the effectiveness of jasmonic acid (JA) was compared to three pesticides, abamectin, thiamethoxam, and acetamiprid, against P. citrella infesting mandarin (Citrus reticulata L.) and lime (C. aurantifolia L.) seedlings. Mortality rate was significantly different due to JA and other pesticides treatments. Moreover, on the 3rd day after treatment, JA demonstrated the highest reduction percentage of leafminer (77.08 and 33.33%) on mandarin and lime, respectively. By the 10th day after treatment, JA and abamectin displayed 100% reduction in both plant species. Furthermore, the foliar application of JA enhanced the most vegetative characteristics in the treated seedlings, including growth rate (shoot length/root length), fresh and dry weights of shoot and root as well as the number of leaves/seedling. Moreover, soluble protein content was increased significantly under JA treatment in the two Citrus spp. Jasmonic acid showed a good biological activity, which gives a practical reason to recommend it to be integrated in pest management programs as an alternative product for controlling P. citrella.

No abstract

The effect of Salicylic acid (SA) on three Cavendish banana cultivars (i.e. Zeef, imported and local Grand Naine) subjected to in vitro salt stress was evaluated. Five concentrations of NaCl (0,30,60,120 and 200 mM) were tested, among which the optimum concentration for screening was determined at 120 mM. Different concentrations of SA (0, 0.5 and 1 mM) were assessed for several vegetative and physiological traits of the three cultivars cultured upon medium containing 120 mMNaCl. Analysis of variance showed highly significant differences among cultivars, SA concentrations and salinity levels, as well as their interactions in most of the studied traits. NaCl treatment caused severe loss in vegetative and physiological traits in all tested cultivars and activated several protein bands compared with non-saline conditions. Moreover, addition of SA exhibited a beneficial effect in reducingdamage caused by salinity in several traits i.e. survival percentage, plantlet length, fresh weight, total chlorophyll, carotenoids and proline content and Potassiumuptake. In addition, SA at 0.5 mM was more effective in enhancement salinity tolerance, while high concentration inhibited most of protein bands enhanced under salinity. The results showed that among the evaluated cultivars, both Grand Naine cultivars were more tolerantthanZeef cultivar. The information resulted herein is valuable and could be help inimprovement of salt tolerance in banana.