scholarly journals Hybridization Experiments on Three Biotypes of the Brown Planthopper, Nilaparvata lugens (Homoptera : Delphacidae) at the IRRI, the Philippines

1981 ◽  
Vol 16 (3) ◽  
pp. 193-199 ◽  
Author(s):  
Kazushige SOGAWA
1995 ◽  
Vol 16 (1) ◽  
pp. 27-33 ◽  
Author(s):  
K. A. Shufran ◽  
M. E. Whalon

AbstractRandom amplified polymorphic DNA (RAPD) amplified by the polymerase chain reaction (PCR) was used to estimate the relatedness of three biotypes of brown planthopper, Nilaparvata lugens (Stål), from the Philippines. Each individual brown planthopper had a unique set of RAPD bands, but no bands were diagnostic for any one biotype. Brown planthopper types 1, 2 and 3 were genetically homogeneous. This supports results of other studies which conclude that brown planthopper biotypes are not sub-specific categories, but merely represent individual variation for virulence to rice cultivars.


2002 ◽  
Vol 92 (5) ◽  
pp. 431-437 ◽  
Author(s):  
M.J. Way ◽  
G. Javier ◽  
K.L. Heong

AbstractPredatory ants are omnipresent year-round in upland (dryland) rice fields in the Philippines. At least 14 species were identified of which the very aggressive Solenopsis geminata (Fabricius) and also Tapinoma sp. nr indicum Forel usually predominated. Some highly aggressive species, notably Pheidolegeton spp. and Bothriomyrmex dalyi Forel were localized. Solenopsis geminata flourished within many fields, not only during the crop season but also throughout dry season fallows where they remained aggressively predatory. Rice plants infested with brown planthopper Nilaparvata lugens (Stål) were usually found within a few hours and S. geminata workers were quickly recruited to N. lugens aggregates. Predation was usually incomplete and workers began to solicit the few remaining late instar or adult N. lugens survivors. These oviposited but no second generation nymphs appeared. There was a surge of recruited ants at the time of N. lugens egg hatch when surviving adults were also killed. Initially, S. geminata alone killed N. lugens aggregates less quickly than with the whole predator complex but ultimately its sole effect was as great as that of the complex. Scattered N. lugens adults, corresponding to numbers that initially colonize rice plants, were eliminated as quickly by S. geminata alone as by the predator complex. Tapinoma indicum occurring separately or with S. geminata on the same plant contributed to predation of N. lugens especially on young nymphs. Solenopsis geminata attacked other insects on rice notably leaffolders of which 97% mortality was recorded when they were exposed throughout egg and larval stages. The role of S. geminata as a predator of upland rice pests is discussed in the context of known biological control of pests of non-rice dryland crops in the tropics and sub-tropics by S. geminata and other Solenopsis spp.


2020 ◽  
Author(s):  
J. P. Hereward ◽  
X.H. Cai ◽  
A. M. Matias ◽  
G. H. Walter ◽  
C. X. Xu ◽  
...  

AbstractBrown planthoppers (Nilaparvata lugens) are the most serious insect pests of rice, one of the world’s most important staple crops. They reproduce year-round in the tropical parts of their distribution, but cannot overwinter in the temperate areas where they occur, and invade seasonally from elsewhere. Decades of research has not revealed their source unambiguously. We therefore sequenced the genomes of brown planthopper populations from across temperate and tropical parts of their distribution and show that the Indochinese peninsula is the major source of migration into temperate China. The Philippines, once considered a key source, is not significant, with little evidence for their migration into China. We find support for immigration from the west of China contributing to these regional dynamics. The lack of connectivity between the Philippines and mainland China explains the different evolution of Imidacloprid resistance in these populations. This study highlights the promise of whole genome sequence data to understand migration when gene flow is high – a situation that has been difficult to resolve using traditional genetic markers.


2012 ◽  
Vol 40 (4) ◽  
pp. 502-508 ◽  
Author(s):  
M. P. Ali ◽  
Salem S. Alghamdi ◽  
M. A. Begum ◽  
A. B. M. Anwar Uddin ◽  
M. Z. Alam ◽  
...  

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