80 THE PEANUT— THE UNPREDICTABLE LEGUME 



Disease Resistance 



Varietal resistance of peanuts to sclerotium wilt or southern root rot 

 has been reported by Reyes (56). From experiments conducted in the 

 Philippines Reyes concluded : "Different varieties of peanuts grown in 

 an infected field showed varying degrees of infection. Wilting ranging 

 from 31.3 to 50.7 per cent of the plants was noted by actual counts. 



"Varieties used in field inoculation tests showed susceptibility to 

 peanut wilt in the descending order as follows : (a) Valencia ; (b) Maca- 

 pno; (c) Georgia Red; (d) White Improved Spanish; (f). Biit; (g) 

 Cagayan No. 1; (h) San Jose No. 3; (i) Vigan Lupog; (j) Tirik; (k) 

 Tai-tau; (1) Virginia Jumbo; and (m) Virginia Jumbo (a). The least 

 infected varieties were Virginia Jumbo (a), Virginia Jumbo, and Tai-tau 

 while Valencia and Macapno were the most seriously infected." 



Bolhuis (12) stated that A. Rasteiro, A. nambyquarae, and Schwarz 

 21, a selection from native sources, were highly resistant to the slime, 

 disease {Bacterium solanacearum) . Higgins (31) stated that resistance 

 to each of the two leaf spotting fungi is inherited separately and suggested 

 that a single factor is involved in each case. With respect to resistance to 

 Sclerotium rolfsii this author stated that "most of our selections show 

 a high degree of resistance." Reyes and Romasanta (57) reported varia- 

 tions in susceptibility among 16 different varieties to Cercospora 

 personate. The intensity of infection was measured by leaf spot count 

 from a duplicated trial. It was suggested that resistance to this disease 

 might be attained through breeding. 



Breeding 



In 1910 Van der Stok began the breeding work with peanuts in the 

 Netherlands East Indies. In 1938, Bolhuis gave the following as princi- 

 pal objectives in the breeding program: high yield, resistance to slime 

 disease, erect foliage, large seeds, pods with more than two seeds, pods 

 with slight constriction, and early ripening. 



Badami ( 1 ) reported his initial hybridization results with peanuts in 

 1922 and in later annual reports from the Mysore Agricultural Depart- 

 ment he has indicated the results of subsequent selection. 



Patel et. al. (48) reported in 1936 that a breeding program had been 

 been in progress in Madras for about 5 years. Approximately 100 varie- 

 ties were grown in the two annual seasons, irrigated (February- June), 

 "rain-fed" July- January) . 



The economic importance of peanuts, their world production, and a 



