Effect of potassium silicate as a foliar fertilizer on drought tolerance of Pinus Roxburghll Sarg seedlings [electronic resource].

Includes reference

This study was conducted at the nursery of Timber trees and Forestry Department, Horticulture research Station at EI-Kanater EI-Khayria, Qalyubia Governorate, Egypt, during the seasons of 201112012 and 201212013.To study the response of Pinus roxburghii Sarg seedling (one year old) to different irrigation periods (4, 6 and 8 days), affected by potassium silicate at 5,10 and 15 mill as a foliar spray. The results indicated that, irrigation plants at 8 days periods, height growth, stem diameter and biomass fresh and dry weight greatly diminished and these parameters increased due to 4 days irrigation periods. On the other hand, the longest roots correlated with deficit soil moisture content. Total chlorophyll increased in the plants grown under 4 days irrigation period and decreased with 8 days irrigation period. Whereas, total carbohydrate increased at irrigating every 8 days period and the opposite occurred at 4 days.Potassium needles content decreased as soil moisture content decreased, meanwhile, proline content increased in the plants grown under drought stress condition (8 days irrigation). Foliar spray with potassium silicate at rate of 10 or 15m Ill on the plants grown under 8 days irrigation period promoted height, stem diameter growth and biomass fresh and dry weight more than those untreated by potassium silicate and irrigated at 4 days interval. High level of potassium silicate spray combined with water stress 8 days irrigation interval resulted in greatly longest roots compared to those irrigated at 4 days and not spray with potassium silicate fertilizer. Total chlorophyll and total carbohydrate increased due to spray potassium silicate at rate of 10 or 15 mill combined with those irrigated every 6 or 8 days rather than control. Spraying potassium silicate at 10 or 15 mill resulted in progressive values in needles potassium and proline content and its absence caused a reduction in both of them. Therefore it could be recommended that spraying the needles of Pinus roxburghii with potassium silicate at rate of 10 or 15 mill and irrigated every 6 or 8 days as water stress ameliorated most of growth parameters better than those irrigated every 4 days and untreated with potassium silicate, meaning that, it can be used less water in irrigating the plants with spraying potassium silicate.

Summary in arabic.

1