Understanding the pollen and ovule characters and fruit set of fruit crops in relation to temperature and genotype – a review

Abstract

Plant reproduction is indispensable for maintaining crop productivity and species sustainability which basically involves pollen and ovule. Productivity is influenced by temperature stress in various fruit crops worldwide and important factor for unfruitfulness is failure in fertilization. Understanding of the plant reproductive characters in relation to genotype differentiated response across different temperatures will help to develop strategies in overcoming temperature stress. Available literature suggests that variation in pollen viability, germination and tube growth and ovule normality exists among different fruit species, cultivars and flower types (even in the same plant as in litchi) and are strongly influenced by temperature stress and suitable temperature for proper pollen and ovule performance has been identified for various fruit crops. Possible reasons to explain the mechanism for impairment of proper functioning of pollens and ovule are discussed. Further, low and erratic fruit set, improper fruit development and stenocarpic fruits as a result of temperature stress leads to reduced yield. We suggest considering in vitro performance for establishing in vivo nutritional requirements and standardizing critical leaf nutrients by way of correlating with pollen germination, tube growth and ovule normality per cent. Male and female parents can be identified for breeding purpose and region specific adoption based on temperature prevalence in the area.