3 results
Search Results
Now showing 1 - 3 of 3
- The lower yield of tomatoes grown in tunnels, due to the limited space, remains a challenge. Stem training has long been identified as one of the most important horticultural practices used to improve the yield and fruit quality of tomatoes grown in commercial tunnels; however, there is little information available on the domeshaped tunnels that are used, particularly by smallholder farmers. The common stem-training methods used in tunnels include the Single-Stem (SS), the Double-Stem (DS) and the Two-Plants-per-Pot (TPP) methods. Their effect on the plants’ growth, development and physiology varies significantly, and hence, it affects crop productivity. The experiment was conducted in an 8 m 30 m dome-shaped tunnel and the treatment included the single-stem, double-stem and two-plants-per-pot methods. A higher photosynthetic rate was observed in the SS treatment, followed by the DS treatment. Similar trends were found in the growth, yield and fruit quality parameters of the SS and DS treatments. However, the DS and TPP treatments exhibited, on average, a higher number of fruits, as well as a higher colour index, TSS, TA and Brima per harvest, than the SS treatment. The study indicated that the double-stem and two-plants-per-pot training methods are the best for farmers who seek to optimize their yields and maximize their profits for this cultivar.
- 1
- 24
- 0
- Trellising is one of the most important horticultural practices used during the growth and development of tomatoes produced in tunnels and open fields. The effect of different trellising methods was investigated on leaf gaseous exchange and photosynthetic efficiency of fertigated indeterminate tomatoes (Solanum lycopersicum) grown in a dome-shaped tunnel. The experiment was laid out as a randomized complete block design with three treatments, namely, vertical, early layering and late layering trellising methods. The results showed significant differences (p\0.05) amongst the different trellising methods in photosynthetic rate (Pn), intercellular CO2 concentration (Ci), the ratio of intercellular and atmospheric CO2 concentration (Ci/Ca), stomatal limitation, transpiration rate (T), water use efficiency, the maximum quantum efficiency of photosystem II photochemistry (Fv/ Fm), effective quantum efficiency of photosystem II photochemistry (/ PS II), photochemical quenching (qP), electron transportation rate, maximum fluorescence and proportion of open reaction centers (1-qP), indicating variability among tested trellising methods. The findings on leaf gas exchange and chlorophyll fluorescence revealed that early and late layering trellising methods improved photosynthetic efficiency than vertical trellising. Therefore, these results provide some evidence that early and late layering trellising methods are the best methods that can be used by resource-constrained farmers in dome-shaped tunnels to improve the physiological efficiency of indeterminate tomatoes.
- 1
- 17
- 0
- Maize mutants with low phytic acid have a compromised overall agronomic performance that results in low yields. This study was conducted to investigate the effect of P (18, 26 and 34 mg/kg) on the agronomic performance of low and high phytic acid (LPA and HPA) maize synthetic populations of tropical origin, compared to two commercial hybrids (SC701 and LS8520). Subsequently, a germination test was performed on the seeds produced from the different levels of P fertilizer application rates. The germination test was conducted in the laboratory, using a germination paper towel, while the agronomic study was conducted in a controlled environment. The measured parameters included days to 50% flowering, plant height, and grain yield, as well as the final germination and germination velocity index. The results found that the grain yield increased by 1.30, 0.51, 2.41 and 1.87 t/ha in LPA, HPA, SC701 and LS8520, from the application of 18–26 mg/kg of P, respectively. However, there were non-significant differences (p > 0.05) in the grain yields of all varieties at a P application of 26 and 34 mg/kg. The final germination increased by 4% and 2% in LPA and LS8520, respectively, with the increase in the P application rate being from 18 to 26 mg/kg. However, no significant differences (p > 0.05) were found in the final germination percentage of all varieties at 26 mg/kg of P. This study indicated that the optimum application of P at planting enhances the overall performance of the LPA maize synthetic population to a level that is comparable to commercially-grown varieties.
- 1
- 3
- 0