scholarly journals Dynamics of Mean-Variance-Skewness of Cumulative Crop Yield Impact Temporal Yield Variance

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Abdullah A. Jaradat

Farmers' decision to adopt new management or production system depends on production risk. Grain yield data was used to assess production risk in a field experiment composed of two cropping systems (CNV and ORG), each with eight subsystems (two levels each of crop rotation (2-yr and 4-yr), tillage management (conventional, CT and strip, ST), and fertilizer input (fertilized, YF and non-fertilized, NF)). Statistical moments, cumulative yield (CY), temporal yield variance (TYV) and coefficient of variation (CV) were used to assess the risk associated with adopting combinations of new management practices in CNV and ORG. The mean-variance-skewness (M-V-S) statistics derived from yield data separated all 16 subsystems into three clusters. Both cropping systems and clustered subsystems differed as to their ability to maintain a constant yield over years, displayed different yield cumulative probabilities, exhibited significant and different M-V-S relationships, and differed as to the reliability of estimating TYV as a function of CY. Results indicated that differences in management among cropping systems and subsystems contributed differently to the goal of achieving yield potential as estimated by the cumulative density function, and that certain low-input management practices caused a positive shift in yield distribution, and may lower TYV and reduce production risk.

Author(s):  
Alicia Ayerdi Gotor ◽  
Elisa Marraccini

In the Global North, there is an increasing interest in pulses both for their beneficial effects in cropping systems and for human health. However, despite these advantages, the acreage dedi-cated to pulses has been declining and their diversity reduced, particularly in European temperate regions, due to several social and economic factors. This decline has stimulated a political debate in the EU on the development of plant proteins. By contrast, in the Global South, a large panel of minor pulses is still cropped in regional patterns of production and consumption. The aim of this paper is to investigate the for cultivation of potential minor pulses in European temperate regions as a complement to common pulses. Our assumption is that some of these crops could adapt to different pedo-climatic conditions, given their physiological adaptation capacity, and that these pulses might be of interest for the development of innovative local food chains in an EU policy context targeting protein autonomy. The research is based on a systematic review of 269 papers retrieved in the Scopus database (1974–2019), which allowed us to identify 41 pulses as candidate species with a protein content higher than 20% that are already consumed as food. For each spe-cies, the main agronomic (e.g. temperature or water requirements) and nutritional characteristics (e.g. proteins or antinutritional contents) were identified in their growing regions. Following their agronomic characteristics, the candidate crops were confronted with variability in the annual growing conditions for spring crops in European temperate areas to determine the earliest poten-tial sowing and latest harvest dates. Subsequently, the potential sum of temperatures was calcu-lated with the Agri4cast database to establish the potential climatic suitability. For the first time, 21 minor pulses were selected to be grown in these temperate areas and appear worthy of inves-tigation in terms of yield potential, nutritional characteristics or best management practices.


1999 ◽  
Vol 35 (2) ◽  
pp. 153-166 ◽  
Author(s):  
R. J. GUMTANG ◽  
M. F. PAMPOLINO ◽  
T. P. TUONG ◽  
D. BUCAO

A study was conducted from October 1994 to March 1996 to assess groundwater dynamics and quality in relation to landuse and farm input of nitrogen fertilizer in a highly diversified and intensive agricultural area at Magnuang, Batac, Ilocos Norte. Monthly groundwater depths, nitrate-nitrogen (NO3-N), chloride (Cl−), bicarbonate (HCO3−), electrical conductivity (EC) and pH were determined in 19 agricultural and domestic wells. In the dry season, sweet pepper (Capsicum annuum) had a higher irrigation requirement and caused more groundwater level decline than other crops. EC (700–3000 μmho cm−1) and HCO3− (90–500 ppm) in all wells exceeded the FAO threshold quality for irrigation but were not related to farm management practices. Eight wells showed near or above the World Health Organization NO3-N limit (10 ppm) for drinking water. High nitrogen fertilizer input increased the mean NO3-N (r2 = 0.45, p < 0.002). The percentage of the wells' service area under rice cultivation in the wet season accounted for 84% (p < 0.001) of the variation in NO3-N among the wells. The mean NO3-N declined as the percentage of service area under rice increased. This was related to the denitrification process in the flooded fields and the lower levels of nitrogen fertilizer for rice compared with other crops.


1978 ◽  
Vol 29 (5) ◽  
pp. 897 ◽  
Author(s):  
RA Fischer ◽  
R Maurer

With a view to understanding the basis of cultivar differences in yield under drought, a wide range of cereal cultivars representing durum wheats (Triticum turgidum L.), triticales (X Tritosecale Wittmack), barleys (Hordeum vulgare), and especially tall and dwarf bread wheats (T. aestivum L.) were studied in field experiments in north-western Mexico over three seasons. Drought was created in this rain-free environment by permanently terminating irrigation at various stages before anthesis. Control treatments were well watered throughout the growing period. Detailed measurements of plant water status, leaf area and dry matter production, anthesis date, yield components and grain yield were made. This paper presents primarily the grain yield data. Drought levels were such that the mean yield of all cultivars under drought ranged from 37 to 86% of control yield, corresponding to irrigation cut-offs varying from 69 days before mean anthesis date to only 10 days before. In each experiment the grain yield under drought showed highly significant cultivar differences, which appeared consistent between years. Yields were adjusted for drought escape by using a correction factor which ranged from 2.9 to 8.5 g/m2 per day advance in flowering, being greater in experiments with less severe drought. The demonstration of linear relationships between cultivar yield and drought intensity, as indicated by the mean yield of some or all cultivars, prompted the consideration of cultivar yield under drought as the function of yield potential (Yp, yield without drought), drought susceptibility index (S), and intensity of drought. The cultivar groups showing lowest S values (most droughtresistant) were tall bread wheats and barleys; dwarf bread wheats were intermediate, and durum wheats and triticales were the most susceptible. However, because dwarf wheats have a higher yield potential (Yp) than tall bread wheats, it is suggested that, as a group, tall bread wheats would outyield dwarf wheats only under very severe drought. Also there was considerable within-group variability of S and Yp. Cultivar S values were consistent across experiments. Yield responses of tall and dwarf bread wheat groups obtained in these experiments agreed with those seen in extensive international trials under dryland conditions.


Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 128
Author(s):  
Vladimír Rataj ◽  
Jitka Kumhálová ◽  
Miroslav Macák ◽  
Marek Barát ◽  
Jana Galambošová ◽  
...  

Cereals in Europe are mainly grown with intensive management. This often leads to the deterioration of the physical properties of the soil, especially increasing bulk density due to heavy machinery traffic, which causes excessive soil compaction. Controlled traffic farming (CTF) technology has the potential to address these issues, as it should be advantageous technology for growing cereals during climate change. The aim of this study was to compare the yield potential of CTF and standardly used random traffic farming (RTF) technology using yield maps obtained from combine harvester and satellite imagery as a remote sensing method. The experiment was performed on a 16-hectare experimental field with a CTF system established in 2009 (with conversion from a conventional (ploughing) to conservation tillage system). Yield was compared in years when small cereals were grown, a total of 7 years within a 13-year period (2009–2021). The results show that CTF technology was advantageous in dry years. Cereals grown in the years 2016, 2017 and 2019 had significantly higher yields under CTF technology. On the contrary, in years with higher precipitation, RTF technology had slightly better results—up to 4%. This confirms higher productivity when using CTF technology in times of climate change.


Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 170
Author(s):  
Alicia Ayerdi Gotor ◽  
Elisa Marraccini

In Europe, there is an increasing interest in pulses both for their beneficial effects in cropping systems and for human health. However, despite these advantages, the acreage dedicated to pulses has been declining and their diversity has reduced, particularly in European temperate regions, due to several social and economic factors. This decline has stimulated a political debate in the EU on the development of plant proteins. By contrast, in Southern countries, a large panel of minor pulses is still cropped in regional patterns of production and consumption. The aim of this paper is to investigate the potential for cultivation of minor pulses in European temperate regions as a complement to common pulses. Our assumption is that some of these crops could adapt to different pedoclimatic conditions, given their physiological adaptation capacity, and that these pulses might be of interest for the development of innovative local food chains in an EU policy context targeting protein autonomy. The research is based on a systematic review of 269 papers retrieved in the Scopus database (1974–2019), which allowed us to identify 41 pulses as candidate species with protein content higher than 20% that are already consumed as food. For each species, the main agronomic (e.g., temperature or water requirements) and nutritional characteristics (e.g., proteins or antinutritional contents) were identified in their growing regions. Following their agronomic characteristics, the candidate crops were confronted with variability in the annual growing conditions for spring crops in Western European temperate areas to determine the earliest potential sowing and latest harvest dates. Subsequently, the potential sum of temperatures was calculated with the Agri4cast database to establish the potential climatic suitability. For the first time, 21 minor pulses were selected to be grown in these temperate areas and appear worthy of investigation in terms of yield potential, nutritional characteristics or best management practices.


Author(s):  
B.A. Barrett ◽  
M.A. Turner ◽  
T.B. Lyons ◽  
M.P. Rolston ◽  
H.S. Easton

The yield potential of modern forage cultivars is a limit to production from pasture- based agriculture, and may influence profitability. Hybrid vigour has increased yield in a range of plant species, but is only partially captured in conventional forage breeding systems. The objective of this research was to assess the potential for harnessing hybrid vigour in a semi-hybrid breeding system for perennial ryegrass (Lolium perenne). Paired crosses among eight parental sources, including four cultivars and four ecotypes, were used to create 28 semi-hybrid populations. Parents, semi-hybrids and check cultivars were trialled in pure grass plots under rotational grazing for 2 years in the Manawatu. Dry matter yield data were used to estimate cumulative and seasonal patterns of hybrid vigour expression for cultivar x cultivar semi-hybrid combinations. The mean level of high parent heterosis was less than 2%. However, one combination exhibited significant (p


2019 ◽  
Vol 56 (Special) ◽  
pp. 82-91 ◽  
Author(s):  
LV Subba Rao ◽  
RA Fiyaz ◽  
AK Jukanti ◽  
G Padmavathi ◽  
J Badri ◽  
...  

India is the second largest producer of rice in the world and it is the most important staple food grain. All India Coordinated Rice Improvement Project (AICRIP) was initiated with objective of conducting multi-location trials to identify suitable genotypes of high yield potential along with appropriate crop management practices. Since its inception AICRIP contributed significantly in meeting the growing demand both within and outside India. Significant progress has been achieved through AICRIP in terms of varietal release thereby increasing the crop productivity and also meeting the food and nutritional security. This paper makes a sincere effort in bringing out the significant achievements/milestones achieved under the AICRIP program and also gives a few directions for widening the areas under AICRIP.


2019 ◽  
pp. 61-67

Recognition of high yielding and nitrogen (N) fixing groundnut genotypes and desegregating them in the cereal-based cropping systems common in savannah regions will enhance food security and reduce the need for high N fertilizers hence, minimize the high cost and associated environmental consequences. Field trials were conducted during the 2015 growing season at the Research Farms of Bayero University Kano (BUK) and Institute for Agricultural Research (IAR), Ahmadu Bello University, Samaru-Zaria to assess the yield potential and Biolog- ical N fixation in 15 groundnut genotypes (ICG 4729, ICGV-IS 07823, ICGV-IS 07893, ICGV-IS 07908, ICGV- SM 07539, ICGV- SM 07599, ICGV-IS 09926, ICGV-IS 09932, ICGV-IS 09992, ICGV-IS 09994, SAMNUT-21, SAMNUT-22, SAMNUT-25, KAMPALA and KWANKWAS). The groundnut genotypes and reference Maize crop (SAMMAZ 29) were planted in a randomized complete block design in three replications. N difference method was used to estimate the amount of N fixed. The parameters determined were the number of nodules, nod- ule dry weight, shoot and root dry weights, pod, and haulm yield as well as N fixation. The nodule dry weight, BNF, haulm, and pod yield were statistically significant (P<0.01) concerning genotype and location. Similarly, their interac- tion effect was also highly significant. ICGV-IS 09926 recorded the highest nod- ule dry weight of 2.07mg /plant across the locations while ICGV-IS 09932 had the highest BNF value of 140.27Kg/ha. Additionally, KAMPALA had the high- est haulm yield, while ICGV-IS 07893 had the highest pod yield across the loca- tions with a significant interaction effect. The result shows that ICGV-IS 07893 and ICGV-IS 09932, as well as ICGV-IS 09994 and SAMNUT – 22, were the best genotypes concerning BNF, haulm and pod yield in the Northern Guinea and Sudan Savannahs of Nigeria respectively with the potential for a corresponding beneficial effect.


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