RICE farming is in Bedari Sissou’s blood.The 22-year-old from Bodjekali Village in Malanville District,750 km north of Benin’s administrative capital Cotonou,was born into a rice farming family.After completing his ...RICE farming is in Bedari Sissou’s blood.The 22-year-old from Bodjekali Village in Malanville District,750 km north of Benin’s administrative capital Cotonou,was born into a rice farming family.After completing his schooling,展开更多
Studies were conducted during the 2001 and 2002 cropping years at Edozhigi and Sachi in the Southern Guinea Savannah of Nigeria to study the effect of following rice with another crop on the next rice crop. There were...Studies were conducted during the 2001 and 2002 cropping years at Edozhigi and Sachi in the Southern Guinea Savannah of Nigeria to study the effect of following rice with another crop on the next rice crop. There were twelve treatments consisting of poor, good and excellent weed management and pesticidal applications against (AfRGM and diseases set up in a randomized complete block design, in twelve plots in 3 replicates. Results showed that rice treated with gramular isazofos at 0.75 kg a.i. ha–1 and benomyl at 1.0 kg/ha at 20 and 40 days after transplanting (DAT), with good weed management and a follow up crop after rice reduced AfRGM occurrence and disease incidence with a consequent increase in yield of the next rice crop. In 2001 infestation of rice by ARGM was more at Sachi than Edozhigi, while in 2002 there was low ARGM occurrence at the two locations. Brown leaf spot was high at the two locations in the two years of the trial while leaf blast was checked by the integrated control methods used in the study. Higher yields were (1.7 - 11.9 t·ha) from treated-well weeded plots that were cropped to cowpea after the 2001 rice harvest Ludwigia decurens, Sphanoclea geylanica Cyperus difformis and Lepllocidia chinensis were the widely occurring weed species at Edozhigi site while Cyperus difformis, Ipomea mvolucrata, F. awuata and Firnbristylis litoralis were weed species prevalent at Sachi site. The rice nematode, hirschmanniella sp. was recorded at the Sachi site along with other nematodes but was absent at the Edozhigi site. The net benefit farmers would derive for following this rice-dry-season crop sequence vary from US$ 172 - 427 and US$ 175 - 265 ha–1 at Sachi and Edozhigi respectively.展开更多
African cultivated rice,Oryza glaberrima,is characterized by its glabrous glumes.During domestication,the pubescent glumes of its wild ancestor,Oryza barthii,lost their trichomes,and in this study,we show that glabrou...African cultivated rice,Oryza glaberrima,is characterized by its glabrous glumes.During domestication,the pubescent glumes of its wild ancestor,Oryza barthii,lost their trichomes,and in this study,we show that glabrous glume 5(GLAG5),a WUSCHEL-like homeobox transcription factor gene on chromosome 5,is required for trichome development.DNA methylation associated with an hATtransposable element inserted in the promoter region of GLAG5 is found to reduce its expression,leading to the formation of glabrous glumes and leaves in African cultivated rice.Among 82 African cultivated rice varieties investigated in this study,59(approximately 71%)lines exhibit glabrous glumes and harbor the hAT transposon;however,the other 23 varieties(approximately 29%),which exhibit pubescent glumes,lack the hAT transposon,indicating that glag5 had undergone strong artificial selection.Theπ;/π;ratios also show the hAT transposon insertions influence the genetic diversity of an approximately 150-kb interval encompassing the GLAG5 locus.The identification of the GLAG5 gene provides new insights into the domestication of cultivated rice in Africa.We speculate that the selection of varieties with mutations in their promoter regions is an important aspect of crop domestication.展开更多
文摘RICE farming is in Bedari Sissou’s blood.The 22-year-old from Bodjekali Village in Malanville District,750 km north of Benin’s administrative capital Cotonou,was born into a rice farming family.After completing his schooling,
文摘Studies were conducted during the 2001 and 2002 cropping years at Edozhigi and Sachi in the Southern Guinea Savannah of Nigeria to study the effect of following rice with another crop on the next rice crop. There were twelve treatments consisting of poor, good and excellent weed management and pesticidal applications against (AfRGM and diseases set up in a randomized complete block design, in twelve plots in 3 replicates. Results showed that rice treated with gramular isazofos at 0.75 kg a.i. ha–1 and benomyl at 1.0 kg/ha at 20 and 40 days after transplanting (DAT), with good weed management and a follow up crop after rice reduced AfRGM occurrence and disease incidence with a consequent increase in yield of the next rice crop. In 2001 infestation of rice by ARGM was more at Sachi than Edozhigi, while in 2002 there was low ARGM occurrence at the two locations. Brown leaf spot was high at the two locations in the two years of the trial while leaf blast was checked by the integrated control methods used in the study. Higher yields were (1.7 - 11.9 t·ha) from treated-well weeded plots that were cropped to cowpea after the 2001 rice harvest Ludwigia decurens, Sphanoclea geylanica Cyperus difformis and Lepllocidia chinensis were the widely occurring weed species at Edozhigi site while Cyperus difformis, Ipomea mvolucrata, F. awuata and Firnbristylis litoralis were weed species prevalent at Sachi site. The rice nematode, hirschmanniella sp. was recorded at the Sachi site along with other nematodes but was absent at the Edozhigi site. The net benefit farmers would derive for following this rice-dry-season crop sequence vary from US$ 172 - 427 and US$ 175 - 265 ha–1 at Sachi and Edozhigi respectively.
基金supported by the National Natural Science Foundation of China(31925029)。
文摘African cultivated rice,Oryza glaberrima,is characterized by its glabrous glumes.During domestication,the pubescent glumes of its wild ancestor,Oryza barthii,lost their trichomes,and in this study,we show that glabrous glume 5(GLAG5),a WUSCHEL-like homeobox transcription factor gene on chromosome 5,is required for trichome development.DNA methylation associated with an hATtransposable element inserted in the promoter region of GLAG5 is found to reduce its expression,leading to the formation of glabrous glumes and leaves in African cultivated rice.Among 82 African cultivated rice varieties investigated in this study,59(approximately 71%)lines exhibit glabrous glumes and harbor the hAT transposon;however,the other 23 varieties(approximately 29%),which exhibit pubescent glumes,lack the hAT transposon,indicating that glag5 had undergone strong artificial selection.Theπ;/π;ratios also show the hAT transposon insertions influence the genetic diversity of an approximately 150-kb interval encompassing the GLAG5 locus.The identification of the GLAG5 gene provides new insights into the domestication of cultivated rice in Africa.We speculate that the selection of varieties with mutations in their promoter regions is an important aspect of crop domestication.
