Role Played by Community,Farmers and Government during Eradication and Suppression of Bactrocera dorsalis(Diptera:Tephritidae)in Mopani District Municipality in Limpopo Province,South Africa

Bactrocera dorsalis syn Bactrocera invadens(Diptera:Tephritidae)(B.dorsalis)is a quarantine pest of Asian origin with host plants such as Mango(Mangifera indica),Guava(Psidium guajava),Citrus(Citrus spp.)and Papaya(Carica papaya).B.dorsalis is considered as a major threat to many countries due to its ability to establish and spread to new areas,the damage it causes to hosts and potential impact on market access.Due to this threat,the DALRRD(Department of Agriculture,Land Reform and Rural Development)placed traps to monitor B.dorsalis in Mopani District Municipality in 2010.The traps were serviced once a month.A single male specimen of B.dorsalis was detected for the first time on 27 April 2012,in the Deerpak area in Mopani District Municipality,of the Limpopo Province,South Africa.Other incursions occurred in Letsitele and Hoedspruit in the same district,in December 2012.Subsequent to the detections,the DALRRD initiated delimiting surveys.A quarantine area was implemented to regulate the removal of host fruits to contain the pest and to initiate an eradication program.The eradication and suppression methods focused on applications of BAT(Bait Application Technique),MAT(Male Annihilation Technique)and orchard sanitation.An integrated approach was followed by involving several role players which included rural communities,farmers,industry organizations,DALRRD and LDARD(Limpopo Department of Agriculture and Rural Development).After the initial detection in 2012,B.dorsalis was again detected in Deerpak and Letsitele in 2013,but,not in Hoedspruit.In 2014 however,B.dorsalis was detected in all three areas with higher numbers in summer,with the highest number of 11,953,2,260 and 8 in Deerpak,Hoedspruit and Letsitele,respectively.This increase could have been attributed to the higher than normal rainfall and reduced phytosanitary efforts in some areas by affected parties.The results of this study revealed that B.dorsalis can be successfully eradicated and or suppressed provided that role players work together and invest their efforts and resources in an area-wide approach.

Growth and feed efficiency of range performance tested beef bulls in the arid sweet bushveld of South Africa

Data consisting of test performance records of 725 bulls was analysed to evaluate trends for growth and feed efficiency, and to determine environmental factors that influence growth of range performance tested bulls in the arid sweet bushveld of South Africa. Performance data were subjected to regression procedures to estimate parameters of the slope (β) and intercept (α) for average daily gain (ADG) and Kleiber ratio (KR). Mixed procedures were applied to test for sources of variation in ADG and KR. There was an increase of 3.481 g/day/year and 0.528 g/day/ year in ADG for Nguni and Bonsmara bulls, respectively. The ADG trends’ respective feed efficiency as reflected by KR was 0.093 and 0.059. Herd of origin and test-year were the sources of variation for ADG while the variation in KR was due to the herd of origin, test-year, start-age and start-weight. Results indicated a steady increase in ADG and KR for range performance tested bulls in the arid sweet bushveld.

Soil carbon storage and stratification under different tillage/residue-management practices in double rice cropping system

The importance of soil organic carbon（SOC） sequestration in agricultural soils as climate-change-mitigating strategy has become an area of focus by the scientific community in relation to soil management.This study was conducted to determine the temporal effect of different tillage systems and residue management on distribution, storage and stratification of SOC, and the yield of rice under double rice（Oryza sativa L.） cropping system in the southern China.A tillage experiment was conducted in the southern China during 2005–2011, including plow tillage with residue removed（PT0）, plow tillage with residue retention（PT）, rotary tillage with residue retention（RT）, and no-till with residue retention on the surface（NT）.The soil samples were obtained at the harvesting of late rice in October of 2005, 2007 and 2011.Multiple-year residue return application significantly increased rice yields for the two rice-cropping systems; yields of early and late rice were higher under RT than those under other tillage systems in both years in 2011.Compared with PT0, SOC stocks were increased in soil under NT at 0–5, 5–10, 10–20, and 20–30 cm depths by 33.8, 4.1, 6.6, and 53.3%, respectively, in 2011.SOC stocks under RT were higher than these under other tillage treatments at 0–30 cm depth.SOC stocks in soil under PT were higher than those under PT0 in the 0–5 and 20–30 cm soil layers.Therefore, crop residues played an important role in SOC management, and improvement of soil quality.In the 0–20 cm layer, the stratification ratio（SR） of SOC followed the order NT〉RT〉PT〉PT0; when the 0–30 cm layer was considered, NT also had the highest SR of SOC, but the SR of SOC under PT was higher than that under RT with a multiple-year tillage practice.Therefore, the notion that conservation tillage lead to higher SOC stocks and soil quality than plowed systems requires cautious scrutiny.Nevertheless, some benefits associated with RT system present a greater potential for its adoption in view of the multiple-year environmental sustainability under double rice cropping system in the southern China.