Long-term seasonal forecasting of a major migrant insect pest: the brown planthopper in the Lower Yangtze River Valley.

Rice planthoppers and associated virus diseases have become the most important pests threatening food security in China and other Asian countries, incurring costs of hundreds of millions of US dollars annually in rice losses, and in expensive, environmentally harmful, and often futile control efforts. The most economically damaging species, the brown planthopper, (Hemiptera: Delphacidae), cannot overwinter in temperate East Asia, and infestations there are initiated by several waves of windborne spring or summer migrants originating from tropical areas in Indochina. The interaction of these waves of migrants and synoptic weather patterns, driven by the semi-permanent western Pacific subtropical high-pressure (WPSH) system, is of critical importance in forecasting the timing and intensity of immigration events and determining the seriousness of subsequent planthopper build-up in the rice crop.

Brassinosteroids mediate susceptibility to brown planthopper by integrating with the salicylic acid and jasmonic acid pathways in rice.

Improved knowledge of the interactions between plants and insects will facilitate better insect control in crops. Brassinosteroids (BRs) play a vital role in plant growth, developmental processes, and responses to pathogen infection, but the role of BRs in interactions between plants and insects remain largely unknown. In this study, we characterized a negative role of BRs in rice defense against brown planthopper (BPH, Nilaparvata lugens) and examined its underlying mechanisms.

Marker assisted pyramiding of two brown planthopper resistance genes, Bph3 and Bph27 (t), into elite rice Cultivars.

Background: Brown planthopper (BPH) is the most destructive insect in rice production. Breeding of resistant cultivars is the most cost-effective and environment-friendly strategy for BPH management; however, resistant cultivars are currently hampered by the rapid breakdown of BPH resistance. Thus, there is an urgent need to use more effective BPH resistance genes or pyramiding different resistance genes to develop more durable resistant rice cultivars.

STV11 encodes a sulphotransferase and confers durable resistance to rice stripe virus.

Rice stripe virus (RSV) causes one of the most serious viral diseases of rice (Oryza sativa L.), but the molecular basis of RSV resistance has remained elusive. Here we show that the resistant allele of rice STV11 (STV11-R) encodes a sulfotransferase (OsSOT1) catalysing the conversion of salicylic acid (SA) into sulphonated SA (SSA), whereas the gene product encoded by the susceptible allele STV11-S loses this activity.

Detection of quantitative trait loci (QTLs) for resistances to small brown planthopper and rice stripe virus in rice using recombinant inbred lines.

Small brown planthopper (SBPH) and rice stripe virus (RSV) disease transmitted by SBPH cause serious damage to rice (Oryza sativa L.) in China. In the present study, we screened 312 rice accessions for resistance to SBPH.

Genetic dissection of the resistance to Rice stripe virus present in the indica rice cultivar 'IR24'.

Rice stripe disease, caused by Rice stripe virus (RSV) and transmitted by the small brown planthopper (Laodelphax striatellus Fallen), is one of the most serious viral diseases of rice in temperate East Asian production regions. Prior quantitative trait loci (QTL) mapping has established that Oryza sativa L. subsp.

Fine mapping of qSTV11(KAS), a major QTL for rice stripe disease resistance.

Rice stripe disease, caused by rice stripe virus (RSV), is one of the most serious diseases in temperate rice-growing areas. In the present study, we performed quantitative trait locus (QTL) analysis for RSV resistance using 98 backcross inbred lines derived from the cross between the highly resistant variety, Kasalath, and the highly susceptible variety, Nipponbare. Under artificial inoculation in the greenhouse, two QTLs for RSV resistance, designated qSTV7 and qSTV11(KAS), were detected on chromosomes 7 and 11 respectively, whereas only one QTL was detected in the same location of chromosome 11 under natural inoculation in the field.

[Community structure and its dynamics of predatory arthropod in different tobacco varieties fields].

With principal component analysis and using community structural characteristic indices, this paper studied the community structure and its dynamics of predatory arthropod in fields planted with tobacco varieties Nc89, Nc82 and K326. The results showed that in all test fields, spiders and predatory insects were the predominant components of the predatory arthropod community, and their relative abundances were 83.25%-86.

[Spatial structure of populations Myzus persicae and its predatory natural enemy Erigonidium graminicola].

In this paper, the spatial construction models of populations M. persicae and its predatory natural enemy E. graminicola during different periods were simulated by geostatistics, and their spatial relationships were analyzed.

[Effects of imidacloprid on arthropod community structure in tobacco field].

The effects of imidacloprid on the structure of arthropod community and its sub-communities were analyzed. The results showed that after applied imidacloprid, the species number of arthropod community and its pest sub-community was influenced, but that of its natural insect enemy and spider sub-community was not influenced obviously. The individuals of arthropod community and its pest sub-community in both treatment plot (II) and control plot were decreased after the application of imidacloprid on May 23 to June 13, and the decline degree in treatment plot was larger than that in control plot.

[Chaotic diagnosis of Nilaparvata lugens occurrence system].

It is estimated that there are nearly 20 million hectares of rice crop being infested by Nilaparvata lugens, with an annual loss of some half a million tones of grain. In order to study the properties and laws of Nilaparvata lugens occurrence system further, the time series data of Nilaparvata lugens occurrence from 1986 to 1998 collected in Taihu Lake District were analyzed by using the methods of autocorrelation function, power spectrum figure, phase trajectory figure, poincare section, and return map of chaos theory. The results indicated that Nilaparvata lugens occurrence system in Yangtze River valley area in China had an obvious chaotic property, even though there was some interference of random noises.

[Detection and analysis of QTL for resistance to the brown planthopper, Nilaparvata lugens (Stål), in rice (Oryza sativa L.), using backcross inbred lines].

A mapping population of 98 BC1F9 lines (backcross inbred lines: BILs), derived from a backcross of Nipponbare (japonica)/Kasalath (indica)//Nipponbare by the single-seed descent methods, was used to detect quantitative trait loci (QTL) for resistance to brown planthopper (BPH), Nilaparvata lugens (Stål). Seedbox Screening Technique (SST) was applied to evaluate the reactions of two parents and 98 BILs to BPH at the seedling stage, and the entries were graded on ratio of dead seedlings. A total of three QTL controlling BPH resistance were detected on chromosomes 2, 10 and 12, respectively.