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This paper designed a systematic evaluation methodology to study the regional comprehensive production capacity of hog industry in China. A three-layer evaluation index system of comprehensive production capacity of hog industry was established. The index system included 26 indicators and mainly covered seven respects, namely natural resource condition, feed supply capacity, current status of hog production, costs and returns of hog production, agricultural foundation, support capability of animal science and technology, and ecological environment condition. Then based on the index system, applied entropy weight method, grey relational analysis and principal component analysis, the comprehensive production capacity of hog industry of 31 provinces and municipalities in China in 2000, 2005 and 2010 was evaluated respectively. The consistency of these three methods was examined by Mann-Kendall test. A combined evaluation was conducted and reasons led to the great variation in ranking for some provinces and municipalities during the period of 2000-2010 were analyzed. Applied hierarchical clustering method, 31 provinces and municipalities were divided into four groups and the regions which were appropriate for hog farming and which were not were figured out.

ABSTRACTHibiscus chlorotic ringspot virus (HCRSV) possesses a novel open reading frame (ORF) which encodes a putative 23-kDa protein (p23). We report here the in vivo detection of p23 and demonstrate its essential role in viral replication. The expression of p23 could be detected in protein extracts from transfected kenaf (Hibiscus cannabinusL.) protoplasts and in HCRSV-infected leaves. Further, direct immunoblotting of infected kenaf leaves also showed the presence of p23, and transient expression in onion and kenaf cells demonstrated that the protein is distributed throughout the cell. Site-directed mutagenesis showed that mutations introduced into the ORF of p23 abolished viral replication in kenaf protoplasts and plants but not in Chenopodium quinoaL. The loss of function of the p23 mutant M23/S33-1 could be complemented in transupon the induced expression of p23 from an infiltrated construct bearing the ORF (pCam23). Altogether, these results demonstrate that p23 is a bona fide HCRSV protein that is expressed in vivo and suggest that p23 is indispensable for the host-specific replication of HCRSV. In addition, we show that p23 does not bind nucleic acids in vitro and does not act as a suppressor of posttranscriptional gene silencing in transgenic tobacco carrying a green fluorescent protein.

ABSTRACTHibiscus chlorotic ringspot virus (HCRSV) from naturally infected Hibiscus rosa-sinensisL. loses virulence in its experimental systemic host Hibiscus cannabinusL. (kenaf) after serial passages in a local lesion host Chenopodium quinoa. Here we report the genetic changes responsible for the loss of virulence at the molecular level. A remarkable covariation of eight site-specific amino acids was found in the HCRSV capsid protein (CP) after serial passages in C. quinoa: Val49?Ile, Ile95?Val, Lys270?Arg, Gly272?Asp, Tyr274?His, Ala311?Asp, Asp334?Ala, and Ala335?Thr. Covariation of at least three of the eight amino acids, Val49, Ile95, and Lys270, caused the virus to become avirulent in kenaf. Interestingly, the nature of the covariation was consistent and reproducible at each serial passage. These data indicate that the nonsynonymous substitutions of amino acids in the HCRSV CP after serial passages in C. quinoaare not likely to be random events but may be due to host-associated positive selection or accelerated genetic drift. The observed interdependence among the three amino acids leading to avirulence in kenaf may have implications for structural or functional relationships in this virus-host interaction.