Producing enough tomato to meet market demand sustainably has not been feasible in the tropics like Ghana. Attempts to improve production using gre</span><span style="font-family:Verdana;">enhous...Producing enough tomato to meet market demand sustainably has not been feasible in the tropics like Ghana. Attempts to improve production using gre</span><span style="font-family:Verdana;">enhouse facilities have not addressed the challenge because of high-</span><span style="font-family:Verdana;">temperature conditions in the greenhouse, which are difficult to manage. Heat stress, arising from high temperatures, hinder the performance of tomato in terms of fruit set and yield. Moreover, the impending climate change is expected to impose more unfavorable environmental conditions on crop production</span><span style="font-family:Verdana;">. An experiment was conducted in (greenhouse at Chiba Un</span><span style="font-family:Verdana;">iversity, Japan) summer period, which has similar high-temperature conditions like Ghana. This work sought to increase the yield of a hea</span><span style="font-family:Verdana;">t-tolerant tomato using a state-of-the-art hydroponic system thr</span><span style="font-family:Verdana;">ough high-density planting. The outcome of this work was intended for adoption and practice in Ghana. A Heat-tolerant tomato “Nkansah HT” along with Lebombo and Jaguar cultivars, were grown at high and low plant densities (4.1 and 2.7 plants m</span><sup><span style="font-family:Verdana;">-2</span></sup><span style="font-family:Verdana;"> respectively).</span></span><a name="_Hlk72355905"></a><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">Each plant was grown in a low substrate volume culture (0.5 L plant</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) </span><a name="_Hlk72267699"></a><span style="font-family:Verdana;">in a recirculating nutrient film technique (NFT) hydroponic system</span></span><span style="font-family:""><span style="font-family:Verdana;">. Parameters measured were plant growth and dry matter assimilation at 12 week</span><span style="font-family:Verdana;">s after transplanting, and the generative components. Results sh</span><span style="font-family:Verdana;">owed that a high plant density increased plant height but reduced chlorophyll content by</span><span style="font-family:Verdana;"> 9.6%. </span></span><span style="font-family:Verdana;">Under temperature stress conditions, the three cultivars reco</span><span style="font-family:Verdana;">rded more than 95% fruit set, but plant density did not affect the fruit set and the incidence of blossom end rot (BER).</span><span style="font-family:Verdana;"> The incidence of BER reduced the marketable yield of the Jaguar cultivar by 51% but, this physiological disorder was not recorded in the HT and the Lebombo cultivars. A high-density planting increased the yield per unit area increased by 38.9%. However, it is uneconomical to cultivate the Jaguar cultivar under a heat stress condition due to its high susceptibility to blossom end rot. To improve the yield of tomatoes under tropical heat stress with a threatening climate change condition, the HT is a better cultivar suited for high-density planting. This study shows that high-density cultivation of the HT cultivar in NFT hydroponic system has the potential to increase Ghana’s current tomato yield by 4.8 times.展开更多
in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6～35.6℃) and 10 km running (WBGT 25.0～31.1℃) were performed in laboratory and field under hot climate.Ten to twelve ...in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6～35.6℃) and 10 km running (WBGT 25.0～31.1℃) were performed in laboratory and field under hot climate.Ten to twelve times (days) of training were carried out展开更多
This paper reports the effects of two trainings-5 km cross-country race and 15 min heat-bath on theimprovement of heat-tolerance. All subjects of the training group were asked to perform a training once daily for 10to...This paper reports the effects of two trainings-5 km cross-country race and 15 min heat-bath on theimprovement of heat-tolerance. All subjects of the training group were asked to perform a training once daily for 10to 12 d within two weeks. The results proved that the cross-country race training both in the artificial hot chamberand on the drill ground of troop could obtain evident training-adaptation. The rectal temperature, heart rate, andsweat volume reduced by 0. 39℃, 13. 2 b/min and 338 g during training in field, respectively. In the same period ofcross-country race training, the normal military exercises, labours and natural heat acclimatization in the summercould only raise slightly the level of heat acclimatization in soldiers. Heat-bath training could reduce rectal temperature by 0. 6℃ during immersion in hot water, however, the level of heat-tolerance in a hot climatic chamber was inferior to that attained by cross-country race, march and running training.展开更多
文摘Producing enough tomato to meet market demand sustainably has not been feasible in the tropics like Ghana. Attempts to improve production using gre</span><span style="font-family:Verdana;">enhouse facilities have not addressed the challenge because of high-</span><span style="font-family:Verdana;">temperature conditions in the greenhouse, which are difficult to manage. Heat stress, arising from high temperatures, hinder the performance of tomato in terms of fruit set and yield. Moreover, the impending climate change is expected to impose more unfavorable environmental conditions on crop production</span><span style="font-family:Verdana;">. An experiment was conducted in (greenhouse at Chiba Un</span><span style="font-family:Verdana;">iversity, Japan) summer period, which has similar high-temperature conditions like Ghana. This work sought to increase the yield of a hea</span><span style="font-family:Verdana;">t-tolerant tomato using a state-of-the-art hydroponic system thr</span><span style="font-family:Verdana;">ough high-density planting. The outcome of this work was intended for adoption and practice in Ghana. A Heat-tolerant tomato “Nkansah HT” along with Lebombo and Jaguar cultivars, were grown at high and low plant densities (4.1 and 2.7 plants m</span><sup><span style="font-family:Verdana;">-2</span></sup><span style="font-family:Verdana;"> respectively).</span></span><a name="_Hlk72355905"></a><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">Each plant was grown in a low substrate volume culture (0.5 L plant</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) </span><a name="_Hlk72267699"></a><span style="font-family:Verdana;">in a recirculating nutrient film technique (NFT) hydroponic system</span></span><span style="font-family:""><span style="font-family:Verdana;">. Parameters measured were plant growth and dry matter assimilation at 12 week</span><span style="font-family:Verdana;">s after transplanting, and the generative components. Results sh</span><span style="font-family:Verdana;">owed that a high plant density increased plant height but reduced chlorophyll content by</span><span style="font-family:Verdana;"> 9.6%. </span></span><span style="font-family:Verdana;">Under temperature stress conditions, the three cultivars reco</span><span style="font-family:Verdana;">rded more than 95% fruit set, but plant density did not affect the fruit set and the incidence of blossom end rot (BER).</span><span style="font-family:Verdana;"> The incidence of BER reduced the marketable yield of the Jaguar cultivar by 51% but, this physiological disorder was not recorded in the HT and the Lebombo cultivars. A high-density planting increased the yield per unit area increased by 38.9%. However, it is uneconomical to cultivate the Jaguar cultivar under a heat stress condition due to its high susceptibility to blossom end rot. To improve the yield of tomatoes under tropical heat stress with a threatening climate change condition, the HT is a better cultivar suited for high-density planting. This study shows that high-density cultivation of the HT cultivar in NFT hydroponic system has the potential to increase Ghana’s current tomato yield by 4.8 times.
文摘in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6～35.6℃) and 10 km running (WBGT 25.0～31.1℃) were performed in laboratory and field under hot climate.Ten to twelve times (days) of training were carried out
文摘This paper reports the effects of two trainings-5 km cross-country race and 15 min heat-bath on theimprovement of heat-tolerance. All subjects of the training group were asked to perform a training once daily for 10to 12 d within two weeks. The results proved that the cross-country race training both in the artificial hot chamberand on the drill ground of troop could obtain evident training-adaptation. The rectal temperature, heart rate, andsweat volume reduced by 0. 39℃, 13. 2 b/min and 338 g during training in field, respectively. In the same period ofcross-country race training, the normal military exercises, labours and natural heat acclimatization in the summercould only raise slightly the level of heat acclimatization in soldiers. Heat-bath training could reduce rectal temperature by 0. 6℃ during immersion in hot water, however, the level of heat-tolerance in a hot climatic chamber was inferior to that attained by cross-country race, march and running training.
基金Supported in part by grants from the National Natural Science Foundation of China(NSFC)(30300238,30571193)Natural science Foundation of Jiangsu province(BK2004418)+2 种基金Hi-Tech Key project of Jiangsu province(BG2005314)Shanghai Agricultural Committee of China(2004-NO.9-1)key project of National Key Laboratory of Crop Genetics and Germplasm Enhancement(ZW2004-12)
