DETERMINATION OF HERBAGE YIELD AND QUALITY OF DIFFERENT SOYBEAN VARIETIES

Objectives of the present study are to determine the variations in forage yield and quality of soybean cultivars. Experiments were conducted in randomized complete blocks design with 3 replications during the growing season of 2016. A total of 10 cultivars were used as the plant material of the experiments (Bravo, A3127, Traksoy, İlksoy, Mersoy, Nova, SA-88, Arısoy, Safir, Atakişi). Cultivars had a significant effect on yield and chemical composition. Results revealed that green herbage yields varied between 826.39 - 1199.17 kg/da, dry hay yields between 247.71 - 357.90 kg/da, crude protein yields between 16.91 - 39.86 kg/da, acid detergent fiber (ADF) ratios between 26.56 - 34.61%, neutral detergent fiber (NDF) ratios between 38.43 - 44.85%, crude ash contents between 7.20 - 11.22%, crude protein contents between 6.66 - 13.53%, dry matter digestibility (DDM) values between 61.94 - 68.21%, dry matter intake (DMI) values between 2.68 - 3.12% and relative feed values (RFV) between 2.68 - 3.12. The results of the study showed that A3127 cultivar was found to be prominent with green herbage yield (1199.17 kg/da) and dry hay yield (357.90 kg/da) and Safir cultivar was found to be prominent with crude protein yield (39.86 kg/da). It was concluded that the soybean cultivars A3127 and Safir could be recommended for hay production.

Improving Accuracy of Herbage Yield Predictions in Perennial Ryegrass with UAV-Based Structural and Spectral Data Fusion and Machine Learning

High-throughput field phenotyping using close remote sensing platforms and sensors for non-destructive assessment of plant traits can support the objective evaluation of yield predictions of large breeding trials. The main objective of this study was to examine the potential of unmanned aerial vehicle (UAV)-based structural and spectral features and their combination in herbage yield predictions across diploid and tetraploid varieties and breeding populations of perennial ryegrass (Lolium perenne L.). Canopy structural (i.e., canopy height) and spectral (i.e., vegetation indices) information were derived from data gathered with two sensors: a consumer-grade RGB and a 10-band multispectral (MS) camera system, which were compared in the analysis. A total of 468 field plots comprising 115 diploid and 112 tetraploid varieties and populations were considered in this study. A modelling framework established to predict dry matter yield (DMY), was used to test three machine learning algorithms, including Partial Least Squares Regression (PLSR), Random Forest (RF), and Support Vector Machines (SVM). The results of the nested cross-validation revealed: (a) the fusion of structural and spectral features achieved better DMY estimates as compared to models fitted with structural or spectral data only, irrespective of the sensor, ploidy level or machine learning algorithm applied; (b) models built with MS-based predictor variables, despite their lower spatial resolution, slightly outperformed the RGB-based models, as lower mean relative root mean square error (rRMSE) values were delivered; and (c) on average, the RF technique reported the best model performances among tested algorithms, regardless of the dataset used. The approach introduced in this study can provide accurate yield estimates (up to an RMSE = 308 kg ha−1) and useful information for breeders and practical farm-scale applications.

Effect of fungal endophytes on plant growth and nutrient uptake in Trifolium subterraneum and Poa pratensis as affected by plant host specificity

The introduction of well-adapted species, such as Trifolium subterraneum (subclover) and Poa pratensis (Kentucky bluegrass), might enhance the forage yield and quality of dehesa pastures for feeding livestock. However, the climatic hardness and poor soils in these agrosystems may limit plant establishment and development. Since fungal endophytes have been found to alleviate the environmental stresses of their host, the aim of this study was to assess the effect of five isolates on forage yield, nutritive value, and plant mineral uptake after their inoculation in the two abovementioned plant species. Two experiments were established (under greenhouse and field conditions) using plants inoculated with two isolates in 2012/2013 (Epicoccum nigrum, Sporormiella intermedia) and three isolates in 2013/2014 (Mucor hiemalis, Fusarium equiseti, Byssochlamys spectabilis). Fusarium equiseti (E346) increased the herbage yield of T. subterraneum under greenhouse conditions, and B. spectabilis improved the forage quality of T. subterraneum by reducing fiber content and of P. pratensis by increasing crude protein. S. intermedia increased the mineral uptake of Ca, Cu, Mn, Pb, Tl, and Zn in subclover, and M. hiemalis increased the uptake of K and Sr in Kentucky bluegrass. These results evidence the potential of the studied fungal endophytes to enhance herbage yield and nutritional value of forage, although further studies should include all of the target forage species as certain host specificity in the effect was observed.

Potassium and Phosphorus Fertilizer Impacts on Alfalfa Taproot Carbon and Nitrogen Reserve Accumulation and Use During Fall Acclimation and Initial Growth in Spring

Phosphorus (P) and potassium (K) impact alfalfa (Medicago sativa L.) performance, but how these nutrients alter taproot physiology during fall acclimation and subsequent growth in spring is unclear. Our objectives were to: (1) determine seasonal patterns for taproot P and K concentrations during fall acclimation and during initial shoot growth in spring; (2) determine how P and K nutrition impacts accumulation of taproot C and N reserves during fall and their subsequent use when shoot growth resumes in spring; and (3) assess how addition of P and K fertilizer impacts survival and shoot growth in spring. Two P (0 and 75 kg ha−1) and two K (0 and 400 kg ha−1) treatments were applied and taproots were sampled between September and December, and again from March to May over 2 years. Concentrations of taproot sugar, starch, buffer-soluble protein, amino-N, and RNA pools were determined. While P and K fertilizer application increased taproot P and K concentrations two- to three-fold, concentrations of P and K in taproots over time did not change markedly during cold acclimation in fall, however, taproot P declined in spring as plant growth resumed. Compared to the 0K-0P treatment, taproots of plants fertilized with 400K-75P had higher starch, protein, amino-N, and RNA, but reduced sugar concentrations in fall. Concentrations of all these pools, except starch, declined during the initial 2 weeks of sampling beginning in late March as shoot growth resumed in spring. Herbage yield in May was highest for the 400K-75P treatment and least for the 0K-0P treatment, differences that were associated with variation in mass shoot−1 and not shoots m−2. High yield of the 400K-75P plants in May was consistently associated with greater concentrations and use of amino-N, soluble protein, and RNA pools in taproots, and not with accumulation and use of starch and sugar pools. Understanding factors leading to the accumulation of taproot N reserves and RNA during cold acclimation in fall and their use during the initial growth in spring should enhance efforts to improve alfalfa growth and herbage yield in spring.

RELATIONSHIPS BETWEEN FORAGE YIELD AND CHARACTERS IN SOME NARBONNE VETCH (VICIA NARBONENSIS L.) CULTIVARS SOWN IN EARLY SPRING AT SUBTROPICAL CONDITIONS

The aim of this research was to determine relationships among forage yield and its some characters in Narbonne vetch cultivars sown in early spring at subtropical conditions. This investigation was conducted between 2016-2018 years at Tekirdağ Namık Kemal University, Faculty of Agriculture, Field Crops Department Research and Experimental Area in randomized complete block design with three replications. Three Narbonne vetch (Bozdağ, Dikili and Özgen) cultivars were used. The plant height, number of branches per plant, stem diameter, number of leaves per plant were determined in ten plants. The plant height, number of branches per plant, stem diameter, number of leaves per plant, herbage and hay yields ranged from 40.75-43.09 cm, 1.67-2.72, 5.70-6.57 mm, 10.27-13.73 t ha-1 and 2.28-2.89 t ha-1, respectively, in Narbonne vetch cultivars. A statistically significant and positive relationships were determined between herbage yield and hay yield, between stem diameter and herbage yield and between stem diameter and hay yield. The correlation coefficients analysis showed that the strongest effective trait on herbage yield in Narbonne vetch was the stem diameter. Stem diameter trait can be considered as the primary selection criteria for improving herbage yield in Narbonne vetch at early spring sowing in similar ecological conditions

Studies on impact of canopy temperature on growth and yield of pigeonpea + kalmegh intercropping system

A field experiment was conducted at Nagarjun Medicinal Garden, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola during 2009-10 to determine suitable row proportion for pigeonpea + kalmegh intercropping system. Canopy temperature showed decreasing pattern with the advancement in age of the crop. Maximum thermal use efficiency (TUE) in pigeonpea and kalmegh was noticed with 2:1 (3.43 kg/ha/DºC) and 1:1 (0.72 kg/ha/DºC) row proportion. Dry matter and grain yield of pigeonpea recorded positive and negative correlation respectively with canopy temperature. While, herbage yield, seed yield and andrographoloide yield of kalmegh recorded positive correlation with morning canopy temperature and negative correlation with evening canopy temperature.

Effect of Fungal Endophytes on Plant Growth and Nutrient Uptake in Trifolium Subterraneum and Poa Pratensis as Affected by Plant Host Specificity

The introduction of well-adapted species, such as Trifolium subterraneum and Poa pratensis, might enhance the forage yield and quality of dehesas pastures for feeding livestock. However, the climatic hardness and poor soils in these agrosystems may limit plant establishment and development. Since fungal endophytes have been found to alleviate the environmental stresses of their host, the aim of this study was to assess the effect of five isolates on forage yield, nutritive value and plant mineral uptake after their inoculation in the two above-mentioned plant species. Two experiments were established (under greenhouse and field conditions) using plants inoculated with two isolates in 2012/2013 (Epicoccum nigrum, Sporormiella intermedia) and three isolates in 2013/2014 (Mucor hiemalis, Fusarium equiseti, Byssochlamys spectabilis). Thus, F. equiseti (E346) increased the herbage yield of T. subterraneum under greenhouse conditions, B. spectabilis was found to improve the forage quality of T. subterraneum by reducing fibre content and of P. pratensis by increasing crude protein. Also, S. intermedia increased the mineral uptake of Ca, Cu, Mn, Pb, Tl and Zn in subclover and M. hiemalis, the uptake of K and Sr in Kentucky bluegrass. These results evidenced the potential of the studied fungal endophytes to enhance herbage yield and the forage nutritional value, although further studies should include all of the intended forage species as certain host specificity in the effect was observed.