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Table 5. Relationship between time of harvest, spores produced by Beauveria bassiana 9002 cultured on wet rice, spore concentration and the production of wet and dry rice necessary to treat a number of coffee trees and hectares.
Harvest period (Days after inoculation) Spore powder* produced per kg of wet rice (g) Spore concentration in the spore powder harvested (spores/gram) Spore production per kg of wet rice (spores) Production of rice to treat 5000 coffee trees using (= 1 x 1010 spore/tree)
Wet production of rice (kg) Ratio wet to dry Dry production of rice (kg)
1 ha 1000 ha 1 ha 1000 ha
A B C D E F G H I
15 9.5 5.7 x1010 5.4 x1011 92.3 92,336 2.4 39.2 39,197
25 9 5.0x1010 4.5 x 1011 111.1 111,111 2.4 45.6 45,556
35 8.5 2.0x1010 1.7 x1011 294.1 294,118 3.2 92.5 92,500
45 8 3.0x01010 2.4 x 1011 208.3 208,333 3.8 55 55,000

*Based on 200 g of wet rice and after Bb cultured on rice was dried and the spore powder was harvested. The figures given in the above Table were calculated using the data for Bb 9002 isolate harvested manually.
A = For each period of harvested spores, spore powder weight was obtained and the spore concentration per gram was estimated.
B = The mean spore powder harvested at 15 days was 1.9 g from 200 g of wet rice, thus the spore powder harvested from 1000 g of wet rice will be 9.5 g.
C = The mean concentration of spores per gram of powder harvested at 15 days was 5.7 x 1010 spores/gram.
D = B x C: 9.5 g x 5.7 x 1010 spores/g = 5.4 x 1011 spores.
E = kg wet rice x spores (ha)/spores (1 kg wet rice): 1 kg x 5 x 1013 spores/5.4 x 1011 spores = 92.3 kg/ha of wet rice.
F = E x 1000 ha.
G = Is the ratio between wet rice + B. bassiana culture and dried rice + B. bassiana culture.
H = E/H: 92.3 kg/2.4 = 39.2 kg.
I = F/H: 92 336/2.4 = 39 197 kg.
The number of spores produced by 1 kg of dry rice was established as follows: (dose/ha)/H = 5 x 1013/39.2 = 1.3 x 1012/2.4 (ratio wet/dry) = 5.4 x 1011 spores/kg of dry rice. It has the same number of spores as 1 kg of wet rice.
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