Effects of soil management, pollination, and nitrogen fertilizers on Williams' pear trees

1969 ◽  
Vol 9 (40) ◽  
pp. 553
Author(s):  
A Selimi ◽  
JC Keatley

The effect of soil management, pollination, and level and timing of nitrogen fertilizer on mature spurpruned Williams' pear trees under irrigated conditions was studied. The dominant response was due to soil management; straw mulch was better than cultivation, and cultivation was equal to clover sward in yield, but was inferior in vigour. Cross pollination improved yield, and tended to depress growth for both straw mulch and clover sward plots, but had little or no effect in cultivation. The various nitrogen treatments produced no important differences except that unfertilized trees declined in growth though not in yield, and the growth decline was slower than expected. After the fertilizer trials were concluded, the clover sward treatment was lifted in production to almost equal straw mulch. This improvement was probably due to the introduction of less severe pruning and the use of weedicides along the tree line.

1970 ◽  
Vol 10 (43) ◽  
pp. 218
Author(s):  
A Selimi ◽  
JC Keatley

The effects of soil management, liming (soil pH), and fertilizers on Packham's Triumph and Josephine de Malines pears under irrigation conditions were studied. The management systems were cultivation, straw mulch, bare surface, and white clover sward. The fertilizers were phosphorus and nitrogen (on straw mulch only), potash and nitrogen (on bare surface only), nitrogen on clover sward only, and calcium as agricultural lime and nitrogen (on cultivation only). Treatment effects were expressed as yield or vigour differences between pre-trial and post-trial periods. Packham's gave similar yield of fruit whether on cultivation or straw mulch. The yield from clover sward and bare surface was much lower than from straw mulch trees. Tree vigour was best under straw mulch and similar within the other treatments. For Josephine, all treatments yielded equally, but tree vigour was best under straw mulch plots. Packham's under bare surface and receiving the highest dressing of potassium sulphate yielded better than the unfertilized trees. Josephine under straw mulch and receiving the highest dressing of superphosphate yielded better than unfertilized trees. Under clover sward, Packham's receiving no artificial nitrogen had lower yield than those receiving standard dressing of nitrogen (0.7 metric tons per hectare of ammonium sulphate). Under these conditions, there were no differences in the yield of Josephines, whether they had artificial nitrogen or not. Packham's under cultivation had similar yield at pH 5.0, 6.5, or 7.5. Josephines, however, yielded much better at pH 6.5 and 7.5 than at pH 5.0.


Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1241
Author(s):  
Stanko Vršič ◽  
Marko Breznik ◽  
Borut Pulko ◽  
Jesús Rodrigo-Comino

Earthworms are key indicators of soil quality and health in vineyards, but research that considers different soil management systems, especially in Slovenian viticultural areas is scarce. In this investigation, the impact of different soil management practices such as permanent green cover, the use of herbicides in row and inter-row areas, use of straw mulch, and shallow soil tillage compared to meadow control for earthworm abundance, were assessed. The biomass and abundance of earthworms (m2) and distribution in various soil layers were quantified for three years. Monitoring and a survey covering 22 May 2014 to 5 October 2016 in seven different sampling dates, along with a soil profile at the depth from 0 to 60 cm, were carried out. Our results showed that the lowest mean abundance and biomass of earthworms in all sampling periods were registered along the herbicide strip (within the rows). The highest abundance was found in the straw mulch and permanent green cover treatments (higher than in the control). On the plots where the herbicide was applied to the complete inter-row area, the abundance of the earthworm community decreased from the beginning to the end of the monitoring period. In contrast, shallow tillage showed a similar trend of declining earthworm abundance, which could indicate a deterioration of soil biodiversity conditions. We concluded that different soil management practices greatly affect the soil’s environmental conditions (temperature and humidity), especially in the upper soil layer (up to 15 cm deep), which affects the abundance of the earthworm community. Our results demonstrated that these practices need to be adapted to the climate and weather conditions, and also to human impacts.


Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1291
Author(s):  
Nasr M. Abdou ◽  
Mohamed A. Abdel-Razek ◽  
Shimaa A. Abd El-Mageed ◽  
Wael M. Semida ◽  
Ahmed A. A. Leilah ◽  
...  

Sustainability of rice production under flooding conditions has been challenged by water shortage and food demand. Applying higher nitrogen fertilization could be a practical solution to alleviate the deleterious effects of water stress on lowland rice (Oryza sativa L.) in semi-arid conditions. For this purpose, field experiments were conducted during the summer of 2017 and 2018 seasons. These trials were conducted as split-split based on randomized complete blocks design with soil moisture regimes at three levels (120, 100 and 80% of crop evapotranspiration (ETc), nitrogen fertilizers at two levels (N1—165 and N2—200 kg N ha−1) and three lowland Egyptian rice varieties [V1 (Giza178), V2 (Giza177) and V3 (Sakha104)] using three replications. For all varieties, growth (plant height, tillers No, effective tillers no), water status ((relative water content RWC, and membrane stability index, MSI), physiological responses (chlorophyll fluorescence, Relative chlorophyll content (SPAD), and yield were significantly increased with higher addition of nitrogen fertilizer under all water regimes. Variety V1 produced the highest grain yield compared to other varieties and the increases were 38% and 15% compared with V2 and V3, respectively. Increasing nitrogen up to 200 kg N ha−1 (N2) resulted in an increase in grain and straw yields by 12.7 and 18.2%, respectively, compared with N1. The highest irrigation water productivity (IWP) was recorded under I2 (0.89 kg m−3) compared to (0.83 kg m−3) and (0.82 kg m−3) for I1 and I3, respectively. Therefore, the new applied agro-management practice (deficit irrigation and higher nitrogen fertilizer) effectively saved irrigation water input by 50–60% when compared with the traditional cultivation method (flooding system). Hence, the new proposed innovative method for rice cultivation could be a promising strategy for enhancing the sustainability of rice production under water shortage conditions.


Author(s):  
Serra Buchanan

Atmospheric greenhouse gas (GHG) concentrations continue to increase and one of the major culprits is the continued elevation and use of fossil fuels for energy. Using bioenergy, a renewable and sustainable source of natural energy, could help to reduce the effect that fossil fuels are having on the planet by slowing the rate of input of atmospheric GHG’s. Perennial crops such as switch grass can be grown and used as a bioenergy crop. In some cases, nitrogen fertilizers are used to increase the growth of bioenergy crops with potential negative environmental consequences. For example, nitrogen fertilizer can impact soil chemical processes and lead to an increase in the production of greenhouse gases, mainly N2O and CH4. Production of these gases would negate some of the benefits achieved by substituting bioenergy crops for fossil fuels. When I examined the amount of gas flux being produced by switchgrass fields, with 0 lbs/acre, 50 lbs/acre and 150lbs/acre fertilizer treatments we observed, as predicted, an increase in N2O production with more fertilization. In some cases the increase in N2O production in the 150lbs/acre treatment was as extreme as being over 200% larger compared with no fertilization. I also observed some very interesting results with methane production, which has been showing production of methane, along with after around 30 minutes of gas collection in a chamber. Based on the results of my research, I have created a cost benefit analysis of using nitrogen fertilizer on switchgrass crops.


2017 ◽  
Vol 9 (4) ◽  
pp. 236
Author(s):  
Abdulla A. Mohamed Muflahi ◽  
Ahmed Saleh Basuaid

A field experiment was carried out at El-Kod Agricultural Research Station, Abyan Delta, Abyan Governorate during the seasons 2014 and 2015 in soil sandy silt to assess four levels of nitrogen fertilizers (0, 55, 110 and 165 kg N/ha) utilizing urea fertilizer (46% N) on some crop characteristics and efficiency of nitrogen application on two local cultivars of sorghum (Sorghum bicolor L. Moench). Split plot design was applied in four replicates. Fertilizer levels were distributed in main plots whereas, the cultivars in subplots. The results revealed significant differences between cultivars Benny and Saif in all characteristics during the two seasons. Cultivar Benny was significantly superior to cultivar Saif in all crop characteristics, except the length of spike which was significantly superior in Saif cultivar compared to cultivar Benny in both seasons. The increase in nitrogen level led to significant increase in all parameters of crop growth under study in both seasons, where the highest dose of nitrogen (165 kg N/ha) gave highest grain yield (3013 and 3201 kg/ha) in both seasons respectively, while the efficiency of nitrogen utilization declined with increased level of nitrogen application and highest value in nitrogen efficiency (12.78 kg grain/kg N). The interaction between cultivars and nitrogen fertilizer showed significant differences in terms of all studied parameters during both seasons. The cultivar Benny responded to high level of nitrogen (165 kg N/ha) and gave high grain yield (3640 and 3305 kg/ha) in both seasons respectively. The results yielded significant effect for efficiency of nitrogen application on grain yield between the cultivars, the levels of fertilizers and their interaction in the first season whereas, no significant differences were detected in the second season.


Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1816
Author(s):  
Jisheng Zhang ◽  
Tianyi Tong ◽  
Pouwedeou Mouloumdema Potcho ◽  
Suihua Huang ◽  
Lin Ma ◽  
...  

In China, the quantity of nitrogen fertilizer applied is large, but as a consequence of a high level of loss, its utilization rate is low. Compared to common rice, the new giant rice has interesting characteristics, namely high biological yield and good efficient use of fertilizer. However, it becomes urgent to further consider the appropriate rate of nitrogen fertilizer to be applied. The giant rice varieties Feng5 and Feng6 were set up in a pot experiment and a field experiment under five doses of nitrogen fertilizers, namely, 0 kg·ha−1 (CK), 75 kg·ha−1 (T1), 150 kg·ha−1 (T2), 225 kg·ha−1 (T3) and 300 kg·ha−1 (T4). Parameters such as leaf area index (LAI), lodging index (LI), nitrogen utilization rate, photosynthesis rate and grain yield were measured. The results showed that with the increase of nitrogen dose in a certain range, LAI, plant height, the number of tillers, net photosynthetic rate (NPn), the transpiration rate (Tr), and the grain yield increased while the lodging index (LI), the nitrogen agronomic utilization rate (AE) and nitrogen partial productivity (PFPN) decreased. Additionally, with the increase of nitrogen application, the grain yield index (HI) and nitrogen contribution rate (FCRN) of rice presented a parabolic trend.


1966 ◽  
Vol 6 (20) ◽  
pp. 42 ◽  
Author(s):  
FC Crofts

Under supplementary spray irrigation at Badgery's Creek, N.S.W., it has been possible to increase the late autumn, winter, and early spring production of a clover dominant ryegrass-clover pasture by more than 3,000 lb of dry matter an acre by sod-seeding oats with nitrogen fertilizers. The oat seeding rate and the amount of nitrogen fertilizer applied at seeding are critical factors in determining the amount of additional winter forage obtained. At this stage it appears that the sod-seeding of oats at four bushels an acre with about 90 lb of nitrogen an acre in early autumn will greatly increase winter forage production under irrigation at a much lower cost than that associated with hand-feeding.


2019 ◽  
Vol 132 ◽  
pp. 105092 ◽  
Author(s):  
Kashif Akhtar ◽  
Weiyu Wang ◽  
Guangxin Ren ◽  
Ahmad Khan ◽  
Yongzhong Feng ◽  
...  

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