Evaluation of crisphead lettuce cultivars in different cover types by manova and discriminant analysis

In many agricultural experiments the variables are biologically correlated and it is inappropriate to study them only under univariate analysis. Therefore, we evaluated commercial characteristics of crisphead lettuce cultivars and covers under a multivariate approach, using canonical discriminant analysis. We used a split plot design and we tested the cover crop, cultivar and interaction effects by using MANOVA (α= 5%). Means and its standard errors were obtained for average total weight, weight of the head, volume and density of plants. Canonical discriminant analyses were performed using PROC CANDISC procedure in SAS (SAS Institute, 2008) system. Canonical plots were obtained using JMP 9.0 (SAS Institute, 2010) linked to SAS database. With these plots it was possible to note the differences among factors levels. When polyethylene film was used as cover the plants had inferior commercial characteristics than plants in which cover crops were used. Thus, the cover with polyethylene film can be discouraged in the cultivation of crisphead lettuce, promoting environmental sustainability. We suggest these multivariate techniques in horticulture studies.

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Sorghum Accessions for Use as Cover Crops and Biofuel Feedstocks

Journal of Agricultural Studies ◽

10.5296/jas.v3i2.8114 ◽

2015 ◽

Vol 3 (2) ◽

pp. 258

Author(s):

Abram Jared Bicksler ◽

John B Masiunas

Keyword(s):

Discriminant Analysis ◽

Cover Crops ◽

Cover Crop ◽

Germplasm Collection ◽

Field Studies ◽

Canonical Discriminant Analysis ◽

Tiller Number ◽

Canonical Variates ◽

Growth Habits ◽

Landrace Accessions

Phenotypes of sorghum species (Sorghum sp.) have characteristics making them valuable summer annual cover crops and/or biofuel feedstocks for temperate climates. In field studies conducted at Urbana, IL, USA, fourteen USDA sorghum landrace accessions and three commercial sorghum accessions were evaluated for their growth habits and regrowth potential. In Canonical Discriminant Analysis (CDA) analysis, the first two canonical variates were significant and accounted for 86% of the among-accession variability. Unmown tiller number, regrowth tiller number, and regrowth biomass best discriminated between accessions in CDA and scattergrams. The accessions clustered into three subgroups. Three multi-stemmed accessions (two commercial varieties and one USDA accession) with an ability to regrow clustered away from the bulk of the USDA sorghums. Multi-stemmed accessions are useful for breeding improved summer annual cover crops that are tall, produce copious amounts of biomass, and rapidly regrow after defoliation; although propensity to lodging and poor germination of accessions will need attention. Additionally, landrace sorghum accessions in the USDA germplasm collection are useful for breeding cover crop and biofuel feedstocks, due to their great height and biomass production, although it will be necessary to select for improved regrowth potential. Crosses between USDA landraces and the commercially available multi-stemmed accessions could lead to a sorghum cover crop and biofuel plant with great biomass and height and ability to regrow following defoliation.

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Cover crops and their effects on the biomass yield of Serjania marginata plants

Ciência Rural ◽

10.1590/s0103-84782012000400006 ◽

2012 ◽

Vol 42 (4) ◽

pp. 614-620 ◽

Cited By ~ 4

Author(s):

Luciane Almeri Tabaldi ◽

Maria do Carmo Vieira ◽

Nestor Antonio Heredia Zárate ◽

Luan Ramos da Silva ◽

Wander Luiz Farias Gonçalves ◽

...

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Biomass Yield ◽

Block Design ◽

Dry Weight ◽

Randomized Block Design ◽

Tropical Legumes ◽

Conservation Of Natural Resources ◽

Crotalaria Spectabilis ◽

Plot Design

The use of cover crops can reduce or even eliminate the use of nitrogenous fertilizers, contributing to a more sustainable agriculture and ensuring the conservation of natural resources. Thus, the aim of this research was to evaluate the use of cover crops to improve the biomass yield of Serjania marginata plants. The experiment was carried out at the Federal University of Grande Dourados, in Dourados-MS, from December 2009 to February 2011. A split plot design was used in a randomized block design with four replications, being evaluated in plots three species of tropical legumes (Stizolobium aterrimum, Crotalaria spectabilis and Canavalia ensiformes, and one control plot (without cover crops), and in subplots the addition or not of nitrogen (N) (at 150 days after transplant (DAT)). Plants of S. marginata in each subplot were harvested at 240 and 350 DAT. S. aterrimum and C. ensiformes showed higher accumulation of fresh (average of 37.61t ha-1) and dry (average of 6.39t ha-1) biomass of shoot in flowering, compared with the C. spectabilis (21.92 and 4.63t ha-1, respectively). The contribution of cover crops as a likely source of N only was observed for S. aterrimum and C. ensiforme, which promoted an increase in chlorophyll index, leaf area, fresh and dry weight of leaves and stem of S. marginata plants, in absence of N. In leaves of S. marginata, only C. ensiformes contributed significantly to an increase in N levels, while an increase in K levels was observed with all cover crop treatments, when compared to control. Pre-cultivation with S. aterrimum and C. ensiformes provided an increase in P levels in leaves of S. marginata. Therefore, S. aterrimum and C. ensiformes were the most promising cover crops for growing of S. marginata, improving the biomass yield and probably the N economy.

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Respon Padi Gogo Terhadap Residu Pupuk Organik

Agrotek ◽

10.30862/agt.v3i2.566 ◽

2018 ◽

Vol 3 (2) ◽

Author(s):

Baso Daeng

Keyword(s):

Environmental Sustainability ◽

Upland Rice ◽

Organic Fertilizer ◽

Growing Season ◽

Chicken Manure ◽

Good Effect ◽

Best Response ◽

Different Types ◽

Main Plot ◽

Plot Design

The rate of conversion of paddy fields and irrigation water crisis suggest to consider the development of upland rice.� Empowerment of organic-based dryland done to increase rice, as well as environmental sustainability efforts.� The purpose of this experiment was to determine the effect of organic fertilizer residue to upland rice in the second growing season.� Experiments using a split-split plot design.� The main plot consisted of a dosage of 50% and 100% organic fertilizer in the first growing season.� Sub plot consisted of chicken manure (20 tons ha-1), Centrosema� pubescens (4.3 tons ha-1) + chicken manure (10 tons ha-1), and Thitonia diversifolia (4.3 tons ha-1) + chicken manure (10 tons ha-1).� Sub-sub plot consist of Danau Gaung and Batu Tegi varieties.� The different types of fertilizer had no effect on plant productivity.� The addition of Thitonia diversifolia gave a good effect on some growth variable and its resistance due pathogen attack.� Batu Tegi varieties are varieties that give the best response from an organic fertilizer.� Interaction between dosage, type of fertilizer, and varieties do not provide areal impact.

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Cover Crop Contributions to Improve the Soil Nitrogen and Carbon Sequestration in Almond Orchards (SW Spain)

Agronomy ◽

10.3390/agronomy11020387 ◽

2021 ◽

Vol 11 (2) ◽

pp. 387

Author(s):

Miguel A. Repullo-Ruibérriz de Torres ◽

Manuel Moreno-García ◽

Rafaela Ordóñez-Fernández ◽

Antonio Rodríguez-Lizana ◽

Belén Cárceles Rodríguez ◽

...

Keyword(s):

Carbon Sequestration ◽

Soil Erosion ◽

Soil Nitrogen ◽

Cover Crops ◽

Cover Crop ◽

Nitrate Content ◽

Sw Spain ◽

Sequestration Potential ◽

Almond Orchards ◽

Shallow Soils

Almond (Prunus dulcis Mill. [D.A. Webb]) is the third most widely spread crop in Spain and has traditionally been cultivated in marginal areas and shallow soils under rainfed conditions. However, it recently has been progressively introduced in flat irrigated areas. The implementation of cover crops in the inter-rows of woody crops has been proven as a suitable strategy to reduce the runoff and soil erosion but they also can boost soil quality and health. A field experiment was conducted during two-monitoring seasons to examine the soil nitrogen and carbon sequestration potential of three seeded cover crops [barley (Hordeum vulgare L.), hairy vetch (Vicia villosa Roth), and a mixture of 65% barley and 35% vetch] and a control of spontaneous flora in irrigated almond orchards (SW Spain). Here, we show that barley provided the highest biomass amount, followed by mixture covers, vetch, and the control treatment. Also, vetch covered the soil faster in the growing stage, but its residues were decomposed easier than barley and mixture treatments during the decomposition period after mowing, providing less soil protection when the risk of water erosion with autumn rainfall is high. On the other hand, vetch improved soil nitrate content by over 35% with respect to barley and mixture treatments at 0–20 cm soil depth throughout the studied period. In addition, a greater carbon input to the soil was determined in the barley plot. That is, the mixture and barley cover crops had higher potential for carbon sequestration, augmenting the soil organic carbon by more than 1.0 Mg ha−1 during the study period. Thus, taking into consideration the findings of the present experiment, the establishment of a seeded cover crop would be more advisable than spontaneous flora to mitigate soil erosion, enhancing soil fertility and carbon sequestration in irrigated almond plantations in Mediterranean semi-arid regions.

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Quantifying Root-Soil Interactions in Cover Crop Systems: A Review

Agriculture ◽

10.3390/agriculture11030218 ◽

2021 ◽

Vol 11 (3) ◽

pp. 218

Author(s):

Cameron M. Ogilvie ◽

Waqar Ashiq ◽

Hiteshkumar B. Vasava ◽

Asim Biswas

Keyword(s):

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Cover Crops ◽

Cover Crop ◽

Soil Formation ◽

Soil Physical Properties ◽

Nutrient Losses ◽

Complex Interactions ◽

Soil Ecosystems

Plant roots are an integral part of soil ecosystems and contribute to various services, including carbon and nutrient cycling, weathering, and soil formation. They also modify soil physical properties (e.g., soil water content, pore size distribution, and bulk density) and impact subsequent crops’ growth. Cover crops have been reported to improve soil and environmental quality by reducing nutrient losses, improving soil water content, and increasing soil organic matter. Understanding the complex interactions between cover crop roots and soil (RS) is of utmost importance. However, cover crop RS interactions have not been critically reviewed. In this article, we investigated the nature of cover crop physical RS interactions and explored the emerging technologies for their study. We also assessed technologies that may be readily applied to the study of physical RS interactions in cover crop systems and discussed ways to improve related research in the future.

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Organic Farming and Cover-Crop Management Reduce Pest Predation in Austrian Vineyards

Insects ◽

10.3390/insects12030220 ◽

2021 ◽

Vol 12 (3) ◽

pp. 220

Author(s):

Jo Marie Reiff ◽

Sebastian Kolb ◽

Martin H. Entling ◽

Thomas Herndl ◽

Stefan Möth ◽

...

Keyword(s):

Organic Farming ◽

Pest Control ◽

Cover Crops ◽

Cover Crop ◽

Management Practices ◽

Integrated Management ◽

Lobesia Botrana ◽

Management Options ◽

Natural Pest Control ◽

Predation Rates

Habitat simplification and intensive use of pesticides are main drivers of global arthropod declines and are, thus, decreasing natural pest control. Organic farming, complex landscapes, and local vineyard management practices such as implementation of flower-rich cover-crop mixtures may be a promising approach to enhance predator abundance and, therefore, natural pest control. We examined the effect of organic versus integrated management, cover-crop diversity in the vineyard inter-rows, and landscape composition on the natural pest control of Lobesia botrana eggs and pupae. Predation of L. botrana pupae was reduced by organic farming and species-poor cover-crops by about 10%. Predation rates of L. botrana eggs did not differ significantly in any of the studied management options. Dominant predators were earwigs (Forficulidae), bush crickets (Tettigoniidae), and ants (Formicidae). Negative effects of organic viticulture are most likely related to the negative nontarget effects on arthropods related to the frequent sulfur and copper applications in combination with the avoidance of strongly damaging insecticides by integrated winegrowers. While a 10% difference in predation rates on a single pest stage is unlikely to have strong practical implications, our results show that the assumed effectiveness of environmentally friendly agriculture needs to be evaluated for specific crops and regions.

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Detecting Bacterial Biofilms Using Fluorescence Hyperspectral Imaging and Various Discriminant Analyses

Sensors ◽

10.3390/s21062213 ◽

2021 ◽

Vol 21 (6) ◽

pp. 2213

Author(s):

Ahyeong Lee ◽

Saetbyeol Park ◽

Jinyoung Yoo ◽

Jungsook Kang ◽

Jongguk Lim ◽

...

Keyword(s):

Discriminant Analysis ◽

Hyperspectral Imaging ◽

Food Processing ◽

Nearest Neighbor ◽

Hyperspectral Image ◽

Uv Light ◽

Hyperspectral Images ◽

K Nearest Neighbor ◽

E Coli ◽

Discriminant Analyses

Biofilms formed on the surface of agro-food processing facilities can cause food poisoning by providing an environment in which bacteria can be cultured. Therefore, hygiene management through initial detection is important. This study aimed to assess the feasibility of detecting Escherichia coli (E. coli) and Salmonella typhimurium (S. typhimurium) on the surface of food processing facilities by using fluorescence hyperspectral imaging. E. coli and S. typhimurium were cultured on high-density polyethylene and stainless steel coupons, which are the main materials used in food processing facilities. We obtained fluorescence hyperspectral images for the range of 420–730 nm by emitting UV light from a 365 nm UV light source. The images were used to perform discriminant analyses (linear discriminant analysis, k-nearest neighbor analysis, and partial-least squares discriminant analysis) to identify and classify coupons on which bacteria could be cultured. The discriminant performances of specificity and sensitivity for E. coli (1–4 log CFU·cm−2) and S. typhimurium (1–6 log CFU·cm−2) were over 90% for most machine learning models used, and the highest performances were generally obtained from the k-nearest neighbor (k-NN) model. The application of the learning model to the hyperspectral image confirmed that the biofilm detection was well performed. This result indicates the possibility of rapidly inspecting biofilms using fluorescence hyperspectral images.

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1 Alternative heifer development systems utilizing corn residue and cover crops

Journal of Animal Science ◽

10.1093/jas/skaa054.220 ◽

2020 ◽

Vol 98 (Supplement_3) ◽

pp. 128-128

Author(s):

Hannah Speer ◽

Hannah Riley ◽

Robert Cushman ◽

Harvey Freetly ◽

Mary Drewnoski

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Reproductive Tract ◽

Equal Opportunity ◽

Late Summer ◽

Distillers Grains ◽

Winter Period ◽

Dried Distillers Grains ◽

Group Breeding ◽

Corn Residue

Abstract Spring-born heifers (n = 1,012) weaned at 148 ± 17 d were used in a 3-yr study to evaluate performance in winter development systems which utilized cover crop and corn residue grazing. Heifers were assigned to 1 of 3 treatments: grazing corn residue with dried distillers grains (CD) or wheat midds (CW) supplementation, or grazing late summer planted oat-brassica cover crop followed by corn residue supplemented dried distillers grains (CC). Grazing of corn residue (CD and CW) and cover crop (CC) began in early November. Supplementation during the corn residue phase was adjusted to target ~55% of mature BW (338 kg) at breeding. After 63 d, CC were moved to corn residue; on d 77 CD and CW began receiving grower ration. In mid-February (d 98), heifers were comingled and managed in a single group. Breeding season began in June and lasted for 29 d. Prior to corn residue grazing, ADG of CC was greater (0.76 kg/d; P< 0.01) than CD or CW (0.58 kg/d and 0.49 kg/d, respectively). Gain during the last 35 d of the winter period for CC was 0.13 kg/d less than CW (P< 0.01) but not different from CD. Overall winter ADG was greater (P< 0.05) for CC (0.62 kg/d) than CD (0.53 kg/d) or CW (0.50 kg/d). Percent of mature BW prior to breeding was 52% for CC and 50% for CD and CW. May reproductive tract scores did not differ (P=0.26) between CC and CW but were greater (P< 0.05) in CC than CD. Pregnancy rates were affected by treatment (P< 0.01), with CC (76%) being greater than CD (68%) and CW (64%). Utilizing oat-brassica cover crops early in the winter followed by a lower rate of gain while grazing corn residue appear to be effective for developing beef heifers. USDA is an equal opportunity employer and provider.

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Soybean Relative Maturity, Not Row Spacing, Affected Interseeded Cover Crops Biomass

Agriculture ◽

10.3390/agriculture11050441 ◽

2021 ◽

Vol 11 (5) ◽

pp. 441

Author(s):

Hans J. Kandel ◽

Dulan P. Samarappuli ◽

Kory L. Johnson ◽

Marisol T. Berti

Keyword(s):

Spring Wheat ◽

Cover Crops ◽

Cover Crop ◽

Soil Cover ◽

Plant Density ◽

Row Spacing ◽

Winter Rye ◽

Soybean Yield ◽

Early Maturing ◽

Crop Biomass

Adoption of cover crop interseeding in the northwestern Corn Belt in the USA is limited due to inadequate fall moisture for establishment, short growing season, additional costs, and need for adapted winter-hardy species. This study evaluated three cover crop treatments—no cover crop, winter rye (Secale cereale L.), and winter camelina (Camelina sativa (L.) Crantz)—which were interseeded at the R6 soybean growth stage, using two different soybean (Glycine max (L.) Merr.) maturity groups (0.5 vs. 0.9) and two row spacings (30.5 vs. 61 cm). The objective was to evaluate these treatments on cover crop biomass, soil cover, plant density, and soybean yield. Spring wheat (Triticum aestivum L.) grain yield was also measured the following year. The early-maturing soybean cultivar (0.5 maturity) resulted in increased cover crop biomass and soil cover, with winter rye outperforming winter camelina. However, the early-maturing soybean yielded 2308 kg·ha−1, significantly less compared with the later maturing cultivar (2445 kg·ha−1). Narrow row spacing had higher soybean yield, but row spacing did not affect cover crop growth. Spring wheat should not follow winter rye if rye is terminated right before seeding the wheat. However, wheat planted after winter camelina was no different than when no cover crop was interseeded in soybean. Interseeding cover crops into established soybean is possible, however, cover crop biomass accumulation and soil cover are limited.

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Labile carbon and other soil quality indicators in two tillage systems during transition to organic agriculture

Renewable Agriculture and Food Systems ◽

10.1017/s1742170511000147 ◽

2011 ◽

Vol 26 (4) ◽

pp. 342-353 ◽

Cited By ~ 21

Author(s):

David Bruce Lewis ◽

Jason P. Kaye ◽

Randa Jabbour ◽

Mary E. Barbercheck

Keyword(s):

Soil Quality ◽

Cover Crops ◽

Organic Agriculture ◽

Weed Management ◽

Cover Crop ◽

Transition Period ◽

Interactive Effects ◽

Labile Carbon ◽

Initial Field ◽

Soil Attributes

AbstractWeed management is one of the primary challenges for producers transitioning from conventional to organic agriculture. Tillage and the use of cover crops are two weed control tactics available to farmers transitioning to organic management, but little is known about their interactive effects on soil quality during the transition period. We investigated the response of soils to tillage and initial cover crop during the 3-year transition to organic in a cover crop–soybean (Glycine max)–maize (Zea mays) rotation in the Mid-Atlantic region of the USA. The tillage treatment contrasted full, inversion tillage with moldboard plowing (FT) versus reduced tillage with chisel plowing (RT). The cover crop treatment contrasted annual versus mostly perennial species during the first year of the rotation. The experiment was initiated twice (Start 1 and Start 2), in consecutive years in adjacent fields. By the end of the experiment, labile carbon, electrical conductivity, pH and soil moisture were all greater under RT than under FT in both starts. Soil organic matter and several other soil attributes were greater under RT than under FT in Start 1, but not in Start 2, perhaps owing to differences between starts in initial field conditions and realized weather. Soil attributes did not differ between the two cover crop treatments. Combining our soils results with agronomic and economic analyses on these plots suggests that using RT during the organic transition can increase soil quality without compromising yield and profitability.

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