Protected Cultivation 197
long been known to improve soil fertility and plant disease management (Dubey and
Singh 2012).
Compost improve the ability of plants to resist against disease caused by root
pathogen like, Fusarium, Phytophthora, Pythium, Rhizoctonia, etc. and foliar patho-
gens like, Pseudomonas, Colletotrichum, Xanthomonas, etc. Among soil-borne root
pathogens, suppression of Fusarium using composts has been reported earlier (Punja
et al. 2002). The severity of various diseases caused by Fusarium has been reduced
from 20% to 90% using compost amendments. Composts have also been used suc-
cessfully for suppression of Phytophthora crown and root rots of nursery, fruit crops
produced in container media (Aryantha et al. 2000) and field soils (Downer et al.
2001). Addition of compost serves two possible purposes significant for the biologi-
cal control of Phytophthora cinnamomi where it provides a substrate for the growth
of fungal antagonists and creates an environment that promotes enzyme activity
(Downer et al. 2001). The suppression of diseases caused by Pythium spp. has been
well-documented. The severity of diseases caused by the fungus, Pythium was
reduced by 30%–70% when growing media were amended with various compost
products.
17.7 Prosperity
Infection of virus and viral diseases are becoming serious threats to the papaya
industry in India. Papaya is a shy crop to application of pesticides. The net-house-
based production system altered with the need-based use of polyethylene sheet
offers immense scope to enhance papaya fruit production with assured yield and
fruit quality. The intervention of net house will be able to reduce the movement of
vectors of the viral diseases and pests like fruit flies. The papaya crop is damaged
due to frost in the northern part of India which can be protected under greenhouse
cultivation. The protected environment will reduce abnormalities in bisexual flow-
ers of the gynodioecious varieties or hybrids which leads the misshapen fruits with
poor marketability. The papaya fruit yield is around 10 kg/plant which contributes
to 40 t/ha productivity. The favourable growing conditions are able to enhance the
fruiting zone from 0.60 to 1.5 m which facilitates proper space for fruit set, growth
and development. The enhanced fruiting zones also offer retention of 40–65 fruits/
plant with uniform size and quality. Fruit yields of 45–60 kg/plant can be obtained
under protected cultivation, which may lead to higher productivity in a range of
180–240 t/ha (Prakash and Singh 2006).
17.8 Future Prospects
The input use and their effectiveness under protected environment have to be
standardised. The pollinator and pollination is vital for the fruit set and retention
which needs further study under protected conditions. The biotic stresses like
mites and nematodes are major concern in protected production system, and their
dynamics have to be studied. The economic feasibility of the protected produc-
tion system has to be investigated considering the large number of stakeholders as
small and marginal farmers in the country. The challenges to the horticulturists