What are the main effects of heat stresses on plants water relations?5 answersHeat stress significantly impacts plant water relations by affecting transpiration, evapotranspiration, and stomatal conductance. High temperatures can lead to a reduction in transpiration rates, especially during the vegetative growth and flowering bud differentiation stages, resulting in stomatal limitations and inhibited root activity. Additionally, heat stress can cause a decrease in leaf gas exchange, further impacting water relations. The combination of heat stress and water stress can lead to increased root aggregation and reduced plant water uptake efficiency. Understanding these effects is crucial for developing strategies to enhance plant tolerance to high temperatures and maintain proper water balance under heat stress conditions.
How temperature affects tomato production?4 answersTemperature has a significant impact on tomato production. High temperatures can lead to poor fruiting, reduced pollen production, and fruit drop, ultimately resulting in decreased yield. Tomato plants are particularly sensitive to heat stress during sexual reproduction, with developing pollens being the most vulnerable. Increasing average diurnal temperature can affect fruit firmness, size, and composition, including sugar and acid contents. Elevated storage temperature can reduce the shelf life of tomatoes and increase fungal susceptibility. On the other hand, low root-zone temperature can negatively affect root activity, leaf photosynthesis, and biomass accumulation, leading to inhibited growth and development. Understanding the molecular mechanisms underlying heat tolerance and identifying superior genotypes with more tolerance to extreme temperatures are important for developing heat-tolerant tomato cultivars. Breeding programs can also focus on selecting for thermotolerance combined with traits suitable for maintaining and improving fruit quality, shelf life, and pathogen susceptibility under changing climate conditions.
What are the consequences of heat stress on agricultural crops?5 answersHeat stress has significant consequences on agricultural crops. It can lead to reduced crop yields, slower grain filling rates, and shorter grain filling durations. Heat stress during the reproductive phase can cause morphophysiological alterations, biochemical disruptions, and reductions in genetic potential. It can also negatively impact the formation of shoots and roots, as well as early biomass in the vegetative stage. Heat stress can result in reduced grain number and weight, as well as poorer grain quality. Additionally, heat stress can affect fertility and seed-setting rate, seed germination and growth, and overall crop productivity. However, plants have developed mechanisms to adapt to heat stress, including modifications in morphological and growth responses, physiological and biochemical pathways, and changes in enzyme reactions. Understanding the genetic basis of heat stress tolerance and utilizing genetic variability in breeding programs can help develop heat-tolerant crop varieties.
What is heat stress temperature application method in tomato experiment?2 answersHeat stress temperature application methods in tomato experiments varied across the studies. In one study, tomato plants were grown in growth chambers at temperatures of 25 and 45 °C. Another study subjected tomato plants to night temperatures above 21 °C to evaluate heat tolerance. In another experiment, tomato plants were grown in growth chambers at temperatures of 25 and 45 °C. Additionally, a study exposed tomato plants to temperatures of 23 °C (optimal temperature) and 40 °C (heat stress). Lastly, mature green tomatoes were treated with hot air or hot water at temperatures ranging from 35 to 45 °C.
What is common heat stress application method in tomato experiment?4 answersThe common heat stress application method in tomato experiments is the use of hot air or hot water treatments. In one study, mature green tomatoes were treated with single heat stress using hot air or hot water, as well as double heat stress using a combination of hot air and hot water. The results showed that hot air treatment for 6 hours was effective in reducing the rate of water loss in tomatoes during storage. Another study evaluated the influence of elementary sulfur application on tomato physiology and growth under different temperature conditions. The plants were sprayed with sulfur, and the results showed that sulfur application alleviated heat stress and enhanced the morphological, physiological, and biochemical attributes of tomato plants.
How does temperature affect growth rate of tomato plants?4 answersTemperature has a significant impact on the growth rate of tomato plants. High temperatures can lead to morpho-anatomical, physiological, and biochemical changes that affect plant growth and development, potentially resulting in reduced economic yield. The optimum mean daily temperature for tomato plants is around 25-30°C, and exceeding this range can negatively affect plant growth and development. Sub-optimal temperatures can decrease leaf and truss initiation rates, resulting in a lower relative growth rate. Additionally, fruit set can be reduced at sub-optimal temperatures due to poorer pollen quality, and the period between anthesis and ripening of the fruit can increase, leading to larger fruits. Higher temperatures can increase early yield but may cause a delay in later trusses. Overall, temperature plays a crucial role in determining the growth rate and development of tomato plants, with both high and low temperatures having adverse effects on various stages of plant growth.