Inheritance of resistance to soybean cyst nematode races 3 and 14 in soybean RIL and F2 populations

Abstract

-The objective of this work was to evaluate the soybean inheritance of resistance to cyst nematode races 3 and 14. The following populations where evaluated: one population of recombinant inbred lines (RILs) [Hartwig (resistant) x Y23 (susceptible line)] for races 3, 14 and 9; one population of families F 2:3 [M-SOY 8001 (resistant) x MB/BR 46 -Conquista (susceptible)] for race 3; and one population of families F 2:3 [(S5995 (resistant) x BRSMG Renascença (susceptible)] for race 14. In RIL populations, four epistatic genes were identified which conditioned resistance to race 14, and three epistatic ones for resistance to races 3 and 9. The lack of one gene provided moderate resistance under all situations. The highest number of genes for resistance to race 14 points out that genes responsible for lower effects might be involved. In population F 2:3 from M-SOY 8001 x MB/BR 46 -Conquista, one recessive gene for moderate resistance and two recessive genes complete resistance to race 3 were identified. Two recessive genes conditioning moderate resistance to race 14 were identified in population F 2:3 from the crossing S5995 x BRSMG Renascença. These results will be useful in designing crossings, involving these parentals, with higher possibility to accumulating genes that provide resistance to several SCN races.

Marker-assisted selection strategies for developing resistant soybean plants to cyst nematode

“…In the other populations, transgressive segregation occurred only for increase in the number of females (Table 1). This type of segregation was also observed for resistance to SCN race 14, which was attributed to possible effects of gene interaction in the control of resistance (Silva et al 2007a). …”

Selecting soybean resistant to the cyst nematode Heterodera glycines using simple sequence repeat (microssatellite) markers

“…Generating resistant plant is one of the most efficient and economical methods for controlling the soybean cyst nematode (SCN), one of the main causes of soybean yield reduction (Matsuo et al, 2012). However because of the great genetic variability of this nematode species, the continual use of the same resistant plant variety exerts selection pressure for SCN breeds that are capable of parasitizing the said variety; in order to avoid this, it is necessary to increase genetic diversity of resistant soybean plants (Silva et al, 2007). In Brazil, there is a greater variability of SCN breeds than that found in the United States; around 11 breeds have been identified in Brazil, carrying a high number of virulence genes (Dias et al, 2009).…”