Propagation and Layout 71
5.2 Raised Bed Sowing..................................................................
The farmers do not have infrastructure facilities like, poly-house, greenhouse, etc. for
raising of seedlings under protected conditions. They grow the seedlings in field condi-
tions. Seeds are usually treated with 0.1% thiram/cerasin/vitavax and planted in beds
15 cm above ground level that have been organically enriched and fumigated. The
seedlings can be raised in nursery beds (300 cm × 100 cm × 10–15 cm) as well as in
pots or polythene bags. The seed rate is 250–300 g/ha in gynodioecious cultivars and
300–500 g/ha in dioecious cultivars (Ram 1986b). The seeds are sown 1–2 cm deep
in rows 10 cm apart and covered with fine compost or leaf mould or khar (d r ied leaves
of Saccharum) or polythene sheets or dry paddy straw to protect and provide shade
or maintain the moisture under Bihar conditions (Figure 5.2a). The shade must be
removed soon after germination because papaya plants develop poorly if kept shaded.
Light irrigation is provided during the morning hours. Germination may take 10–12
days during summer and rainy season, while during February to March, it takes 25–30
days due to low temperature under North Eastern Plains Zone of India (Figure 5.2b).
Authors observed the effect of temperature on per cent germination and days taken
for germination was evaluated in C. papaya cvs. Pune Selection-3 and Pusa Dwarf
under agro-climatic conditions of North Bihar (Figure 5.3). The highest seed germi-
nation percentage was observed in the month of July (average, 96.8% and 93.0%),
followed by August (average, 94% and 88.5%), whereas the lowest germination per-
centage was observed in the month of January (44.2% and 36.8%) in Pune Selection-3
and Pusa Dwarf, respectively. Minimum number of days (average, 5.17 and 6.33 days)
was taken for germination in the month of July and the maximum number of days
(average, 29.5 and 31 days) was taken in the month of January in both the cultivars,
PS-3 and Pusa Dwarf, respectively. The average maximum germination and seed-
ling height was observed at temperature 29.8°C and 29.5°C during July and August,
respectively, whereas the minimum was found at temperature 14°C and 15.9°C during
January and December, respectively. The suitable time for nursery sowing was July to
August for autumn season crop under subtropical conditions of India.
Papaya seedlings are transplanted 40–45 days after seed sowing when they
are 15–20 cm in height. Transplanting is best done in the evening or on cloudy or
FIGURE 5.2 (See colour insert.) Nursery raising: seed sowing (a), seedlings on raised beds
(b) and seedlings in poly tubes (c).