Responses of Canopy Growth and Yield of Potato Cultivars to Weather Dynamics in a Complex Topography: Belg Farming Seasons in the Gamo Highlands, Ethiopia

Potato is an increasingly important crop in Ethiopia. The Gamo Highlands are one of the large potential potato producing regions in Ethiopia. The growing conditions are different from those in the temperate regions, where most of the agronomical expertise on potato has been developed. The influence of environmental conditions on the crop in the Gamo Highlands is poorly understood. We conducted field trials with eight potato cultivars in six locations and during two seasons. The canopy cover (CC) and plant height (PH) were measured with high temporal resolution and tuber yields were assessed as well. The experiments were conducted near our newly installed weather stations at different elevations. CC and PH were strongly correlated with temperature sum (Tsum). Tuber yields differed among elevations and cultivars. Nevertheless, these differences were poorly explained by environmental variables. We also found that no single cultivar performed best at all elevations. The number of branches was a predictor of yield, suggesting that radiation interception was limiting tuber growth. Tuber yield was optimal when the number of days to crop maturity was around 100–110 days. We conclude that Tsum is a predictor of crop growth, but environmental variables poorly explain yield variations, which calls for further investigation.

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Mixed Planting of Potato Cultivars: Growth, Yield and Leafminer Damage in the Cool Tropics

Experimental Agriculture ◽

10.1017/s0014479700019025 ◽

1991 ◽

Vol 27 (3) ◽

pp. 305-318 ◽

Cited By ~ 2

Author(s):

D. J. Midmore ◽

J. Alcazar

Keyword(s):

Field Experiments ◽

Growth Curves ◽

Growth Yield ◽

Potato Cultivars ◽

Growth And Yield ◽

Tuber Growth ◽

Susceptible Cultivar ◽

Premium Price ◽

Potato Foliage ◽

Intercepted Radiation

SummaryThe influence of planting mixtures of two potato cultivars on the incidence of leafminer fly (Liriomyza huidobrensis (Blanchard)) and on damage to potato foliage, and the effect on growth and yield, was studied in two field experiments in coastal Peru. Climatic differences between the two years of the experiments (1983 and 1984) had a greater effect than did cultivar mixtures on adult fly populations and on the numbers of feeding punctures and pupae per leaflet. Mixtures reduced the number of pupae in the tolerant cultivar, but increased it in the susceptible cultivar; in contrast, mixed planting tended to decrease the adult populations and feeding punctures in the susceptible cultivar of each mixture. In neither year did mixture yields or intercepted radiation exceed those of the highest-yielding sole crop, although land equivalent ratios (LER) reached 1.19. Considering the cultivars' different maturity rates and their tuber growth curves, it is probable that the later maturing cultivar of each mixture was able to exploit available light after, and perhaps even before, senescence of the earlier cultivar. Mixed planting of potato could be beneficial but only to farmers who plant both early and late cultivars, under conditions where the early harvest commands a premium price.

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The Impact of Different Environmental Conditions during Vegetative Propagation on Growth, Survival, and Biochemical Characteristics in Populus Hybrids in Clonal Field Trial

Forests ◽

10.3390/f12070892 ◽

2021 ◽

Vol 12 (7) ◽

pp. 892

Author(s):

Valda Gudynaitė-Franckevičienė ◽

Alfas Pliūra

Keyword(s):

Climate Change ◽

Phenotypic Plasticity ◽

Environmental Conditions ◽

Vegetative Propagation ◽

Genotypic Variation ◽

Hybrid Poplar ◽

Field Trials ◽

Biochemical Traits ◽

Suburban Areas ◽

Growing Conditions

To have a cleaner environment, good well-being, and improve the health of citizens it is necessary to expand green urban and suburban areas using productive and adapted material of tree species. The quality of urban greenery, resistance to negative climate change factors and pollution, as well as efficiency of short-rotation forestry in suburban areas, depends primarily on the selection of hybrids and clones, suitable for the local environmental conditions. We postulate that ecogenetic response, phenotypic plasticity, and genotypic variation of hybrid poplars (Populus L.) grown in plantations are affected not only by the peculiarities of hybrids and clones, but also by environmental conditions of their vegetative propagation. The aim of the present study was to estimate growth and biochemical responses, the phenotypic plasticity, genotypic variation of adaptive traits, and genetically regulated adaptability of Populus hybrids in field trials which may be predisposed by the simulated contrasting temperature conditions at their vegetative propagation phase. The research was performed with the 20 cultivars and experimental clones of one intraspecific cross and four different interspecific hybrids of poplars propagated under six contrasting temperature regimes in phytotron. The results suggest that certain environmental conditions during vegetative propagation not only have a short-term effect on tree viability and growth, but also can help to adapt to climate change conditions and grow successfully in the long-term. It was found that tree growth and biochemical traits (the chlorophyll A and B, pigments content and the chlorophyll A/B ratio) of hybrid poplar clones grown in field trials, as well as their traits’ genetic parameters, were affected by the rooting-growing conditions during vegetative propagation phase. Hybrids P. balsamifera × P. trichocarpa, and P. trichocarpa × P. trichocarpa have shown the most substantial changes of biochemical traits across vegetative propagation treatments in field trial. Rooting-growing conditions during vegetative propagation had also an impact on coefficients of genotypic variation and heritability in hybrid poplar clones when grown in field trials.

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Combined application of ammonium nitrate and goat manure: Effects on soil nutrients availability, Okra performance and sustainable food security

Open Access Research Journal of Life Sciences ◽

10.53022/oarjls.2021.1.1.0108 ◽

2021 ◽

Vol 1 (1) ◽

pp. 021-028

Author(s):

Mukhtar Iderawumi ABDULRAHEEM ◽

Sulaimon Abidemi LAWAL

Keyword(s):

Block Design ◽

Chemical Properties ◽

Soil Nutrient ◽

Field Trials ◽

Sub Saharan Africa ◽

Growth And Yield ◽

Urea Fertilizer ◽

Traditional System ◽

Land Preparation ◽

Goat Manure

Many see organic agriculture as the most sustainable form of farming and as the paradigm for global food production in the future. One of the solutions to food insecurity and malnutrition in Sub-Saharan Africa is to promote local crops, encourage the use of locally source materials as amendment, improve their traditional system of production, and so diversify subsistence crop. The major reasons are the lack of knowledge and skill in land preparation and agronomic practices, weather uncertainties, pest outbreak and above all the use of fertilizer. Hence, this research will be carried out to investigate the effects of integrated application of Urea fertilizer and Goat Manure on soil Nutrient Availability and Okra performance. Field trials were conducted with four treatments replicated three times in a Randomized Complete Block Design (RCBD). The treatments were Control (no Urea, no goat manure), 8t/ha-1 goat manure + 200kg/ha-1 urea fertilizer; 8t/ha-1 goat manure + 175kg/ha-1 urea fertilizer and 8t/ha-1 goat manure + 150kg/ha-1 urea fertilizer. Treatments were applied three weeks after planting by ring method with Urea and goat manure mixed. Soil physical and chemical properties, growth and yield parameters were evaluated. Data were analyzed using Analysis of Variance (ANOVA) and Duncan Multiple Range. 8t/ha-1 goat manure + 200kg/ha-1 urea fertilizer gave the highest plant height, leaf area as well as number of leaves than other treatment. However, the fruits weight, days of 50% flowering, number of fruit, fruits diameter and fruits length were significantly increased at 8t/ha-1 goat manure + 200kg/ha-1 urea fertilizer.

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A, The ESTIMATION OF ECONOMIC THRESHOLDS OF JUNGLE RICE (ECHINOCHLOA COLONA L.) AND FALSE AMARANTH (DIGERA ARVENSIS FORSSK.) IN DIRECT SEEDED RICE

JOURNAL OF WEED SCIENCE RESEARCH ◽

10.28941/pjwsr.v26i4.890 ◽

2020 ◽

Vol 27 (2) ◽

pp. 507-523

Author(s):

Amir Ehsan ◽

Muhammad Ehsan Safdar1 ◽

Amjed Ali

Keyword(s):

Block Design ◽

Dry Weight ◽

Field Trials ◽

Research Area ◽

Growth And Yield ◽

Rice Grain ◽

College Of Agriculture ◽

Competitive Index ◽

Economic Thresholds ◽

Direct Seeded

ABSTRACT There is little understanding about ecological interference of weeds in direct-seeded rice. To get estimates of economic thresholds of two weeds in direct seeded rice, two-year field trials were conducted at research area of College of Agriculture, University of Sargodha, Punjab-Pakistan. Treatments included 0, 22, 44, 66 and 88 plants m-2 densities of each of Echinochloa colona and Digera arvensis laid out in randomized complete block design. Augmented densities of E. colona (0, 22, 44, 66 and 88 weed plants m-2) enhanced its plant dry biomass up to 348 and 353%; and relative competitive index maximally to 80 and 77% in years 2015 and 2016, respectively. While the corresponding increases in plant dry weight and relative competitive index of D. arvensis were 367 and 360% and 79 and 82%. The enhancement in N (up to 258 & 257 %), P (up to 220 & 232%) and K (up to 293 & 301%) uptake in years 2015 and 2016, respectively were made by E. Colona whereas the corresponding increases in N, P and K assimilation by D. arvensis were as far as 265 & 257%, 238 & 233% and 305 & 298%, respectively. The declines in growth and yield of rice were observed in response to growing number of both the weeds. Rice grain yield losses ranged between 9.8 to 80% and 28 to 80% by E. Colona and D. arvensis. The economic thresholds of false amaranth and jungle rice were estimated to be 1.6-1.4 plants m-2 and 2.2-2.6 plants m-2, respectively.

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Yield response of restricted-tillering wheat to transient waterlogging on duplex soils

Australian Journal of Agricultural Research ◽

10.1071/ar03089 ◽

2003 ◽

Vol 54 (10) ◽

pp. 957 ◽

Cited By ~ 13

Author(s):

A. G. Condon ◽

F. Giunta

Keyword(s):

Grain Size ◽

Biomass Production ◽

Wheat Yield ◽

Relative Yield ◽

Field Trials ◽

Growth And Yield ◽

Yield Response ◽

South West ◽

Relative Extent ◽

Before And After

Transient waterlogging during winter and spring reduces wheat yield in many parts of southern Australia. Yield reductions from waterlogging are associated with reduced production and survival of tillers, fewer and smaller fertile tillers, and smaller grain size. Under favourable conditions, wheats that have the tiller-inhibition ('tin') gene produce a lower total number of tillers but a higher proportion of large, productive tillers and larger grains than wheats without this gene. These characteristics of restricted-tillering wheat may contribute to improved yield under transient waterlogging. We compared the growth and yield of the commercial variety Bodallin and 2 Bodallin backcross derivatives containing the 'tin' gene in 8 field trials grown on shallow, duplex soils in 1995 and 1996 at 3 locations in the south-west of Western Australia. Trials were sown at standard (1995) and standard and high (1996) seeding rates. Trial-mean yield ranged from 0.5 to 4.7 t/ha, depending on the occurrence and severity of waterlogging before anthesis and of soil water deficit before and after anthesis. Grain yield of the restricted-tillering (RT) lines averaged only c. 80% of Bodallin. At all sites and seeding rates the RT lines had fewer spikes per m2 (45% fewer, on average) but averaged 44% more grains per spike. In 1996 only, grain weight of the RT lines was 6% greater than of Bodallin. There was no evidence that the relative yield of the RT lines was greater at waterlogged sites than at other sites. Waterlogging reduced the number of fertile spikes of RT lines and of Bodallin to the same relative extent and differences in grains per spike and grain size had little effect on relative yields. Even though harvest index of the RT lines was slightly elevated in some environments, biomass production of the RT lines was low in all environments. We conclude that wheats with the 'tin' gene are unlikely to have a yield advantage under transient waterlogging unless their biomass production can match that of more freely tillering wheats.

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Effect of land-use types on the ecomorphological structure of fish assemblage in distinct mesohabitats of neotropical streams

Biota Neotropica ◽

10.1590/1676-0611-bn-2020-1034 ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

Leonardo Antunes Pessoa ◽

Matheus Tenório Baumgartner ◽

Marcelo Percilio Santana Junior ◽

João Paulo Alves Pagotto ◽

Luiz Gustavo Antunes Pessoa ◽

...

Keyword(s):

Land Use ◽

Urban Environment ◽

Fish Species ◽

Fish Assemblage ◽

Environmental Variables ◽

Environmental Changes ◽

Canopy Cover ◽

Distinct Species ◽

Urban Streams ◽

Land Use Types

Abstract The use and occupation of land by human population substantially influence environmental variables and fish assemblage in streams. However, there is little knowledge on how these changes affect the ecomorphological structure of fish assemblage in mesohabitats. Therefore, we aim to assess whether the land-use types affect the ecomorphological structure of fish assemblage in distinct mesohabitats. Environmental and ichthyofaunistic data were collected in three mesohabitats (rifles, runs, and pools) of five rural and five urban streams. Twenty-one ecomorphological indices were obtained from the mean of linear morphological measurements and areas of the fishes. Subsequently, the Euclidean distance was calculated, based on the ecomorphological indices, between each pair of species, to measure the ecomorphological distances for the mesohabitats of the rural and urban streams. The results show that the urban environment is more harmful to streams than the rural one, due to changes in the environmental variables and decrease in species richness. The main environmental changes found in urban streams were the decrease in canopy cover by riparian vegetation and dissolved oxygen, and the increase in electrical conductivity and bed silting. Also, there was a significant decrease in the morphological similarity between fish species in the mesohabitats of urban streams compared to rural ones. Therefore, we can conclude that the urban environment leads to the loss of morphologically similar fish species in the mesohabitats, with only a few functionally distinct species remaining.

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Rice NIN-LIKE PROTEIN 4 is a master regulator of nitrogen use efficiency

10.1101/2020.01.16.908558 ◽

2020 ◽

Author(s):

Jie Wu ◽

Zi-Sheng Zhang ◽

Jing-Qiu Xia ◽

Alamin Alfatih ◽

Ying Song ◽

...

Keyword(s):

N Uptake ◽

Crop Improvement ◽

Field Trials ◽

Growth And Yield ◽

Wild Type ◽

Inorganic N ◽

Master Regulator ◽

Nitrogen Use ◽

Use Efficiency ◽

N Use

AbstractNitrogen (N) is one of the key essential macronutrients that affects rice growth and yield. Inorganic N fertilizers are excessively used to boost yield and generate serious collateral environmental pollution. Therefore, improving crop N use efficiency (NUE) is highly desirable and has been a major endeavor in crop improvement. However, only a few regulators have been identified that can be used to improve NUE in rice to date. Here we show that the NIN-like protein OsNLP4 significantly improves the rice NUE and yield. Field trials consistently showed that loss-of-OsNLP4 dramatically reduced yield and NUE compared with wild type under different N regimes. In contrast, the OsNLP4 overexpression lines remarkably increased yield by 30% and NUE by 47% under moderate N level compared with wild type. Transcriptomic analyses revealed that OsNLP4 orchestrates the expression of a majority of known N uptake, assimilation and signaling genes by directly binding to the nitrate-responsive cis-element in their promoters to regulate their expression. Moreover, overexpression of OsNLP4 can recover the phenotype of Arabidopsis nlp7 mutant and enhance its biomass. Our results demonstrate that OsNLP4 is a master regulator of NUE in rice and sheds light on crop NUE improvement.

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Enviromic assembly increases accuracy and reduces costs of the genomic prediction for yield plasticity

10.1101/2021.06.04.447091 ◽

2021 ◽

Author(s):

Germano MF Costa-Neto ◽

Jose M F Crossa ◽

Roberto F Fritsche-Neto

Keyword(s):

Phenotypic Variation ◽

Field Trials ◽

Proof Of Concept ◽

Tropical Maize ◽

Early Screening ◽

Environmental Similarity ◽

Genetic And Environmental Factors ◽

Growing Conditions ◽

Algorithm Scheme

Quantitative genetics states that phenotypic variation is a consequence of genetic and environmental factors and their subsequent interaction. Here, we present an enviromic assembly approach, which includes the use of ecophysiology knowledge in shaping environmental relatedness into whole-genome predictions (GP) for plant breeding (referred to as E-GP). We propose that the quality of an environment is defined by the core of environmental typologies (envirotype) and their frequencies, which describe different zones of plant adaptation. From that, we derive markers of environmental similarity cost-effectively. Combined with the traditional genomic sources (e.g., additive and dominance effects), this approach may better represent the putative phenotypic variation across diverse growing conditions (i.e., phenotypic plasticity). Additionally, we couple a genetic algorithm scheme to design optimized multi-environment field trials (MET), combining enviromic assembly and genomic kinships to provide in-silico realizations of the future genotype-environment combinations that must be phenotyped in the field. As a proof-of-concept, we highlight E-GP applications: (1) managing the lack of phenotypic information in training accurate GP models across diverse environments and (2) guiding an early screening for yield plasticity using optimized phenotyping efforts. Our approach was tested using two non-conventional cross-validation schemes to better visualize the benefits of enviromic assembly in sparse experimental networks. Results on tropical maize show that E-GP outperforms benchmark GP in all scenarios and cases tested. We show that for training accurate GP models, the genotype-environment combinations' representativeness is more critical than the MET size. Furthermore, we discuss theoretical backgrounds underlying how the intrinsic envirotype-phenotype covariances within the phenotypic records of (MET) can impact the accuracy of GP and limits the potentialities of predictive breeding approaches. The E-GP is an efficient approach to better use environmental databases to deliver climate-smart solutions, reduce field costs, and anticipate future scenarios.

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Effects of Organic and Inorganic Fertilizers on the Growth and Yield of Kenaf (Hibiscus cannabinus L.) Production in South Western Nigeria

International Journal of Plant & Soil Science ◽

10.9734/ijpss/2021/v33i230408 ◽

2021 ◽

pp. 1-9

Author(s):

S. O. Olanipekun ◽

A. O. Togun ◽

A. K. Adebayo ◽

F. B. Anjorin

Keyword(s):

Seed Yield ◽

Block Design ◽

Field Trials ◽

Fertilizer Application ◽

Hibiscus Cannabinus ◽

Organic Fertilizers ◽

Growth And Yield ◽

Mineral Fertilizers ◽

Inorganic Fertilizers ◽

Organic Fertiliser

Farmers use Inorganic Fertilizers (IF) to improve kenaf yield in Nigeria. However, the detrimental effects of mineral fertilizers and its high cost calls for the use of organic fertilizers that are locally available and environment friendly. Combination of Organic Fertiliser (OF) with IF may reduce the bulkiness of OF while harnessing the benefit of both for higher yields. Field trials were conducted at Ibadan and Ilora in 2013 and 2014 to investigate the effects of combined fertilizers on the growth and yield of kenaf. Organic and IF (NPK 20:10:10) fertilizers as: (i) 160 kg ha-1 (sole organic), (ii) 100 kg ha-1 (sole IFl), (iii) Organic and IF at 50:50 ratio and (iv) control (no fertilizer). The experiment was laid out in Randomized Complete block design (RCBD) and replicated three times. Results showed that plant height (220.17 cm, 216.80 cm) and stem diameter (2.27 cm, 1.16 cm). Bast fiber (2.27 t/ha, 2.27 t/ha) and seed yield (1.69 t/ha, 1.78 t/ha) in Ibadan and Ilora respectively were significantly higher in plots with combined fertilizer. Combined fertilizers had the highest fiber and seed yield above sole application and control (no fertilizer application). Hence it is recommended for kenaf cultivation in Southwest Nigeria.

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Temperature as a key factor for successful inoculation of soybean with Bradyrhizobium spp. under cool growing conditions in Belgium

The Journal of Agricultural Science ◽

10.1017/s0021859618000515 ◽

2018 ◽

Vol 156 (4) ◽

pp. 493-503 ◽

Cited By ~ 3

Author(s):

J. Pannecoucque ◽

S. Goormachtigh ◽

J. Ceusters ◽

J. Debode ◽

C. Van Waes ◽

...

Keyword(s):

Field Trials ◽

Protein Yield ◽

Control Treatment ◽

Rhizobial Symbiosis ◽

Key Factor ◽

Growing Conditions ◽

Set Up ◽

Biological Nitrogen ◽

Intermediate Performance

AbstractBacterial inoculation of soybean seeds to improve biological nitrogen fixation is a well-known practice to achieve higher seed and protein yield with reduced fertilization. The optimal inoculation strategy in temperate regions is unknown because soybeans are rarely cultivated under colder growing conditions. The aim of the present work was to determine the most suitable inoculation strategy for soybean cultivation in Belgium. Field trials were set up with four Bradyrhizobium inoculants (HiStick, Force 48, Biodoz and Optimize) at two locations over 2 years (2014–2015) and compared with a non-inoculated control treatment. In addition, HiStick was tested at three doses and Optimize at two time periods prior to sowing. Under Belgian conditions, all inoculants were effective in establishing rhizobial symbiosis, resulting in increased yield, protein content, protein yield and thousand-grain weight compared with the non-inoculated control. A single dose of HiStick was sufficient to establish symbiosis. Pre-inoculation with Optimize 2 weeks before sowing gave an intermediate performance for most parameters between the non-inoculated control treatment and inoculation with Optimize 24 h prior to sowing. Among the four products tested, Biodoz seemed the best product for inoculation under cool growing conditions. Based on the atpD gene, the bacterial strain of Biodoz showed complete similarity with Bradyrhizobium diazoefficiens, while strains of other products were identified as Bradyrhizobium japonicum. In vitro growing capacity of the Biodoz strain at 8 °C was higher compared with the other strains. Better cold adaptation of the Biodoz strain might be a possible explanation for the better performance of Biodoz in Belgium.

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