Fruit cracking of pomegranate and its relationship with temperature and plant water status in hot arid region of India

Abstract

Cracking of pomegranate fruit is a general problem throughout its growing areas and among all varieties, however, the magnitude of the problem is more in arid region. Relative water content and water potential of leaf as indicative of water stress directly affect the magnitude of cracking in pomegranate fruits. Also, both these physiological parameters are likely to be influenced by high temperature stress as measured by canopy air temperature difference (CATD) and fruit air temperature difference (FATD). Percent fruit cracking in different pomegranate varieties ranged from 18.3% in P23 to 62.6% in Jodhpur Red. However, irrespective of cultivars on an average 36% fruit get cracked under prevailing conditions of experimental site. Canopy temperature was lower than air temperature, whereas, fruit surface temperature was higher than air temperature. Both CATD and FATD were significantly correlated with leaf water potential and relative water content. The cultivar having higher leaf water potential and RWC reflected lowest fruit cracking and vice-versa. Stepwise regression analysis indicated that temperature mediated leaf water potential had direct impact on incidence of fruit cracking in pomegranate as with increasing leaf water potential; cracking percent reduces across the varieties studied in present investigation. Such relationships may help in future to identify suitable cultivars for a specific region as well to adopt suitable preventive measures to reduce fruit cracking in pomegranate.