Horticultural crops as affected by climate change

Climate change is causing substantial effects on horticultural crop productivity as well as quality. The global rise in temperature has forced the farming community for early planting of vegetables and early harvesting of certain fruits. Considering fruit trees, the gradual increase in temperature has disturbed the dormancy breaking process and chilling hours of temperate fruits like apple, peaches, cherry apricots, and many others. This increasing atmospheric temperature has enhanced the evaporative demand, plant transpiration rate, and hence crop water use in certain horticultural crops such as strawberry, blackberry, raspberry, lettuce, spinach, and others. The major elements in climate change such as increasing temperatures, atmospheric CO₂, ozone depletion, UV radiation, heavy metal toxicities, extreme weather events (drought and cold), and changes in the precipitation pattern has markedly affected plant growth and development by modulating various physiological and biochemical mechanisms in horticultural crops. The cultivation of determinate vegetables such as tomato and pepper in the field is becoming difficult and less productive due to early rise in temperature causing flower drop and reduced fruit setting. Vegetable quality may also be affected due to higher O₃ levels, which causes leaf chlorosis and necrosis with premature senescence and subsequent yield reductions. Plantation crops such as tea and coconut are also affected by reduced precipitation and higher temperature. Disease incidence and severity in various horticultural crops such as coffee, cassava, citrus, banana, pineapple, cashew, coconut, and papaya are reported to be affected by climate changing factors. In this chapter, we have discussed different classes of horticultural crops which are affected either positively or negatively by climate change.