scholarly journals Growth and Nutrient Use Efficiencies of Yams (Dioscoreaspp.) Grown in Two Contrasting Soils of West Africa

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Lucien N'Guessan Diby ◽  
Bi Tra Tie ◽  
Olivier Girardin ◽  
Ravi Sangakkara ◽  
Emmanuel Frossard

Fertilization is an important management strategy of yams (Dioscoreaspp.) especially when grown in degraded soils. A field study evaluated the leaf numbers, leaf area indices, crop growth, yields, and nitrogen (N) and potassium (K) use efficiencies ofD. alataandD. rotundatain Côte d'Ivoire when grown in two contrasting soils with and without fertilizer.D. alatahad a lower number of leaves per vine, although leaf area indices were higher, and the leaves were retained for a longer period than inD. rotundata. In all situations, the yields ofD. alatawere significantly higher, and fertilizers promoted growth of shoots, roots, tubers, and, thus, final yields especially in the low fertile savanna soil. The beneficial impact of fertilizer on yields was significantly lower in the fertile forest soils. The nutrient use agronomic efficiencies indicated the impact of both N and K in promoting yields especially under nonfertilized conditions.

HortScience ◽  
1994 ◽  
Vol 29 (10) ◽  
pp. 1133-1135 ◽  
Author(s):  
Charles S. Vavrina ◽  
Kenneth D. Shuler ◽  
Phyllis R. Gilreath

`Jupiter' and `Verdel' bell pepper (Capsicum annuum L.) transplants set to the depth of cotyledon leaves or to the first true leaf yielded more fruit than transplants set to the top of the rootball. Increased yields and early stand establishment criteria (number of leaves, leaf area, plant weight, and plant height) suggest that planting pepper transplants deeper than is now common is commercially beneficial in Florida. Deeper plantings may place pepper roots in a cooler environment and reduce fluctuations in soil temperature. Moderated soil temperature, in conjunction with earlier fertilizer and water acquisition, may give deeper-planted pepper plants a competitive edge in growth.


2017 ◽  
pp. 15-23
Author(s):  
Judith Oyoo ◽  
Edward Mamati, Paul Kinoti, Elijah Ateka ◽  
James Karanja, Miriam Judith Otipa ◽  
Lusike Wasilwa

Bio-stimulators are organic products that have been found to enhance crop growth and productivity through mitigating against biotic and abiotic stresses. Four Cowpea varieties namely K80, M66, KVU 27-1 and Kenya Kunde; commercially released & adopted by local households for vegetable production were used to evaluate the impact of bio-stimulators on growth and leaf yield of cowpea in Juja and Katumani from May to July, 2013. The treatments were arranged in a factorial structure, laid out in an RCBD, which were combination of 9 levels of bio-stimulators, with the 4 cowpea varieties planted per site, and giving a total of 36 treatments for each site replicated 3 times. The plots measured 2.5m by 2.5m with spacing of 60cm by 20cm. Parameters under investigation included germination rate, days to germination, plant height, and number of leaves produced and number of nodules formed. Cultural practices such as weeding and pest control were done as need arose. The results showed that there were significant differences in days to germination, germination rate, plant population, chlorophyll levels, leaf weight, plant height and leaf area but not in leaf area between Juja and Katumani. Earliest germination and highest leaf weight were in Katumai whereas highest plant population, germination rate and chlorophyll levels and leaf area were in Juja. Humates improved germination rate, plant height, leaf weight and nodule development in Juja while seaweed extracts improved days to germination, germination rate, plant height, leaf yield, leaf weight and nodule formation in Katumani. Interaction between site and bio-stimulators was recorded in germination rate, days to germination, plant population and in number of leaves produced. Therefore bio-stimulators should be adopted in production of cowpea leaves particularly offseason for food & nutritional security and increasing household incomes in Kenya


2001 ◽  
Vol 1 ◽  
pp. 866-872 ◽  
Author(s):  
C.J.M. Ondersteijn ◽  
A.G.J.M. Oude Lansink ◽  
G.W.J. Giesen ◽  
R.B.M. Huirne

Dutch nutrient policy aims at reducing leaching of agricultural nutrients by internalizing the negative externalities associated with inefficient nutrient use. This is done by taxation of nitrogen and phosphate surpluses that exceed a hectare-based threshold of maximum-allowed surpluses. One management strategy farmers may use to reduce the nutrient surpluses on their farms is to improve the nutrient efficiency of the agricultural production process. This study employs Data Envelopment Analysis (DEA) to calculate nitrogen and phosphate efficiencies and an overall nutrient efficiency measure for a 3-year panel of 114 Dutch dairy farms. Subsequent analyses show the impact of both farm intensity and nutrient efficiency on the nitrogen and phosphate surpluses. It appears that farm intensity has a positive effect on efficiency, but efficiency and intensity exert opposite influences on nutrient surpluses. This is especially the case for nitrogen. The magnitude of a possible reduction of nitrogen surpluses through a strategy of efficiency improvement is therefore limited by the intensity of the farming system, unless the technology with which nutrients are used by the farming system can be further improved or input/output ratios will be altered.


2018 ◽  
Vol 35 (4) ◽  
pp. 133-136
Author(s):  
R. N. Ibragimov

The article examines the impact of internal and external risks on the stability of the financial system of the Altai Territory. Classification of internal and external risks of decline, affecting the sustainable development of the financial system, is presented. A risk management strategy is proposed that will allow monitoring of risks, thereby these measures will help reduce the loss of financial stability and ensure the long-term development of the economy of the region.


2021 ◽  
pp. 112067212110280
Author(s):  
Maria L Salvetat ◽  
Carlo Salati ◽  
Patrizia Busatto ◽  
Marco Zeppieri

Purpose: To assess ocular pathologies admitted to Italian Emergency Eye Departments (EEDs) during the COVID-19 pandemic national lockdown in 2020 in comparison with the same period in 2019. Methods: Electronic records of all patients presenting at EEDs of two tertiary-care Eye Centers during the COVID-19 national lockdown in Italy (March 10–May 3, 2020) were compared with the equivalent period in 2019. Main outcomes were patient age, gender, and diagnoses. Statistical analysis included unpaired Student t-tests, Poisson regression, and chi-square test. Results: Overall EED visits significantly decreased by 54.1% during the 2020 lockdown compared to 2019 (851 vs 1854, p < 0.001). During lockdown, patients showed comparable mean age (52.8 years in 2020 vs 53.3 years in 2019, p = 0.52) and significant male gender bias (61.1% in 2020 vs 55.8% in 2019, p < 0.0001). The most frequent pathologies were eye inflammations, trauma-related incidents, and spontaneous acute vitreous detachment. Patients with inflammation, headache/hemicrania, and spontaneous subconjunctival hemorrhages were significantly less, whereas those with trauma-related diagnoses were significantly higher during the lockdown as compared with 2019 ( p < 0.05). The proportion of non-urgent visits decreased from 17% in 2019 to 8% in 2020 ( p < 0.001). Conclusions: During the 2020 lockdown, there was a significant reduction of accesses to EED, especially for non-urgent pathologies. Potentially visual function threatening conditions, such as trauma-related pathologies, retinal detachment or ruptures, and wet AMD, showed lower number of cases but higher or stable proportion relative to the total caseload, suggesting a correct and efficient access to ophthalmic health care during the pandemic period.


2021 ◽  
Vol 13 (8) ◽  
pp. 1427
Author(s):  
Kasturi Devi Kanniah ◽  
Chuen Siang Kang ◽  
Sahadev Sharma ◽  
A. Aldrie Amir

Mangrove is classified as an important ecosystem along the shorelines of tropical and subtropical landmasses, which are being degraded at an alarming rate despite numerous international treaties having been agreed. Iskandar Malaysia (IM) is a fast-growing economic region in southern Peninsular Malaysia, where three Ramsar Sites are located. Since the beginning of the 21st century (2000–2019), a total loss of 2907.29 ha of mangrove area has been estimated based on medium-high resolution remote sensing data. This corresponds to an annual loss rate of 1.12%, which is higher than the world mangrove depletion rate. The causes of mangrove loss were identified as land conversion to urban, plantations, and aquaculture activities, where large mangrove areas were shattered into many smaller patches. Fragmentation analysis over the mangrove area shows a reduction in the mean patch size (from 105 ha to 27 ha) and an increase in the number of mangrove patches (130 to 402), edge, and shape complexity, where smaller and isolated mangrove patches were found to be related to the rapid development of IM region. The Moderate Resolution Imaging Spectro-radiometer (MODIS) Leaf Area Index (LAI) and Gross Primary Productivity (GPP) products were used to inspect the impact of fragmentation on the mangrove ecosystem process. The mean LAI and GPP of mangrove areas that had not undergone any land cover changes over the years showed an increase from 3.03 to 3.55 (LAI) and 5.81 g C m−2 to 6.73 g C m−2 (GPP), highlighting the ability of the mangrove forest to assimilate CO2 when it is not disturbed. Similarly, GPP also increased over the gained areas (from 1.88 g C m−2 to 2.78 g C m−2). Meanwhile, areas that lost mangroves, but replaced them with oil palm, had decreased mean LAI from 2.99 to 2.62. In fragmented mangrove patches an increase in GPP was recorded, and this could be due to the smaller patches (<9 ha) and their edge effects where abundance of solar radiation along the edges of the patches may increase productivity. The impact on GPP due to fragmentation is found to rely on the type of land transformation and patch characteristics (size, edge, and shape complexity). The preservation of mangrove forests in a rapidly developing region such as IM is vital to ensure ecosystem, ecology, environment, and biodiversity conservation, in addition to providing economical revenue and supporting human activities.


Author(s):  
Teresa Lanzón Serra ◽  
Amelia Díaz Martínez

This work presents the evaluation of the stress symptoms associated to the task of caring for a dependent relative at home. The role played by variables such as type of caregiver (nurse/non-nurse), the relative dependency level, the number of hours per day dedicated to caring and the years the caregiver had been caring for the relative was studied. The sample was made up of 100 caregivers, and the variables associated to stress studied in the present work were intrusion, avoidance and activation. Results showed that non-nurse caregivers caring for a low dependency relative for a period of less than two years were those suffering a higher impact, with more symptoms associated to stress. Hours caring per day worked as a protective variable of stress, in that those caregivers dedicating a lower number of hours to caring had lower risk of suffering stress symptoms. These results clearly show the stressful impact of the first stages of dependency, even at the lowest level of dependency in a relative, on non-professional caregivers and highlight the need to provide strategies, similar to those shown by professional nurses looking after their own relatives, to reduce stress. This kind of intervention would prepare the caregiver for the future stages when the dependency level in the relatives and the effort caring for them would be higher.


2019 ◽  
Vol 148 (1) ◽  
pp. 63-81 ◽  
Author(s):  
Kevin Bachmann ◽  
Christian Keil ◽  
George C. Craig ◽  
Martin Weissmann ◽  
Christian A. Welzbacher

Abstract We investigate the practical predictability limits of deep convection in a state-of-the-art, high-resolution, limited-area ensemble prediction system. A combination of sophisticated predictability measures, namely, believable and decorrelation scale, are applied to determine the predictable scales of short-term forecasts in a hierarchy of model configurations. First, we consider an idealized perfect model setup that includes both small-scale and synoptic-scale perturbations. We find increased predictability in the presence of orography and a strongly beneficial impact of radar data assimilation, which extends the forecast horizon by up to 6 h. Second, we examine realistic COSMO-KENDA simulations, including assimilation of radar and conventional data and a representation of model errors, for a convectively active two-week summer period over Germany. The results confirm increased predictability in orographic regions. We find that both latent heat nudging and ensemble Kalman filter assimilation of radar data lead to increased forecast skill, but the impact is smaller than in the idealized experiments. This highlights the need to assimilate spatially and temporally dense data, but also indicates room for further improvement. Finally, the examination of operational COSMO-DE-EPS ensemble forecasts for three summer periods confirms the beneficial impact of orography in a statistical sense and also reveals increased predictability in weather regimes controlled by synoptic forcing, as defined by the convective adjustment time scale.


2017 ◽  
Vol 30 (2) ◽  
pp. 412-419 ◽  
Author(s):  
ARTHUR BERNARDES CECÍLIO FILHO ◽  
ALEXSON FILGUEIRAS DUTRA ◽  
GILSON SILVERIO DA SILVA

ABSTRACT The intensive cultivation of vegetables with frequent chemical fertilization may cause accumulation of nutrients in the soil. This, in turn, may reduce crop yields and damage the environment due to contamination of ground water and rivers. Thus, to increase the effects of P (0, 100, 200, 300 and 400 kg ha -1 of P2O5) and K (0, 60, 120, 180 and 240 kg ha-1 of K2O) doses on the growth and productivity of radish cultivars (Sakata 19 and Sakata 25) in a soil with high levels of these nutrients, two experiments were conducted in randomized blocks with the factors cultivars and doses arranged in a 2 x 5 factorial design with three replications. Number of leaves per plant, leaf area, shoot and root dry mass, total and commercial productivity, percentage of cracked roots and P and K contents in the plant and in the soil were evaluated. The Sakata 19 cultivar performed better than the Sakata 25 in both experiments. The fertilization with P or K did not influence the growth and the productivity of both radish cultivars. Therefore, both cultivars of radish evaluated do not need to be fertilized with P and K when planted in a Latosol with high levels of these nutrients.


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