Number Of Stalks Research Articles

Seleksi Mutan Tanaman Lamtoro (Leucaena leucocephala cv. Tarramba) Tahan Kutu Loncat terhadap Lingkungan Kering pada Rumah Kaca

Forage is the main source of feed for ruminants. Forage consists of two types, namely grass and legumes. Leguminosa is a type of forage as a source of protein. One type of legume that is well known by breeders in Indonesia is lamtoro (Leucaena leucocephala cv. Tarramba). This study was aimed to produce candidate mutants of lamtoro drought resistant to acid stress conditions. The experiment in this study used an unbalanced completely randomized design with 6 treatments of 740 different replications based on different sources of lamtoro plant mutants at different levels (P0: 0 n= 89, P1: 100 gy n= 82, P2: 200 gy n= 153, P3:300 gy n=120, P4: 400 gy n= 244, P5: 500 gy n= 52). Variables observed included plant height, number of stalks, leaf loss and stem diameter. The results showed that lamtoro plants irradiated with gamma rays at a level of 200 gy-500 gy were significantly higher than 100 gy irradiation at 10 and 12 days watering, but the diameter of the plants was larger at 100 gy irradiation. It can be watering intervals of 10 days and 12 days on the parameters of height and stem diameter showed that gamma rays irradiation of 400 gy resulted in dry-resistant lamtoro mutant candidates under acid stress condition.
 Key words: gamma rays, lamtoro mutant, watering interval

Elderberry Stalks as a Source of High-Value Phytochemical: Essential Minerals and Lipophilic Compounds

Elderberry (Sambucus nigra L.) consumption has been growing in the last years, generating a large number of stalks (~10% of the berries bunch) that are still under-valorized. This study focused on the evaluation of elderberry stalks as a source of high-value phytochemicals. In this vein, the essential mineral content and lipophilic composition were analyzed for the first time. In addition, the polar fraction was evaluated regarding its total phenolic content (TPC) and antioxidant activity by both 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2-diphenyl-1-picrylhydrazyl hydrate (DPPH) assays. The lipophilic fraction was mainly composed of triterpenic acids (2902.20 mg kg−1 of dry weight (dw)), fatty acids (711.73 mg kg−1 dw) and sterols (288.56 mg kg−1 dw). Minor amounts of long-chain aliphatic alcohols and other components were also detected. Ursolic acid (2265.83 mg kg−1 dw), hexadecanoic acid (219.85 mg kg−1 dw) and β-sitosterol (202.74 mg kg−1 dw) were the major lipophilic components verified. The results of this study also indicated that elderberry stalks might be used as a natural source of essential minerals, particularly calcium, iron and potassium, which are known to play important roles in various body functions. The analysis of the polar fraction also showed that elderberry stalks present TPC as high as elderberry themselves as well as considerable antioxidant activity (1.04 and 0.37 mmol TE g−1 of extract, against respectively ABTS and DPPH radicals). These results highlight the potential of elderberry stalks as a natural source of high-value phytochemicals that may be explored in several fields.

The Effect of Harvest Age On The Physical and Chemical Properties of White Oyster Mushrooms (Pleurotus ostreatus)

Oyster mushrooms have a delicious taste and contain nutrients. One of the popular oyster mushrooms in the community is white oyster mushrooms (Pleurotus ostreatus). The content and characteristics of oyster mushrooms are influenced by the age of harvest. This study aims to determine the effect of oyster mushrooms harvesting age on physical and chemical properties. This study used a completely randomized design. The treatment is the age of harvesting namely 2, 3, 4, and 5 days after budding. Each experimental unit was repeated 3 times. This research consisted of nursery, incubation, maintenance, and harvesting oyster mushroom. The results showed that harvest age has a significant effect on the height, diameter of the hood and the wet weight but has no effect on the number of stalks and water content of white oyster mushrooms

Effect of plot size and plant spatial arrangement on the efficiency of family selection in sugarcane

The purpose of this study was to identify the ideal sample size representing a family in its potential, to identify superior families and, in parallel, determine in which spatial arrangement they may have a better accuracy in the selection of new varieties of sugarcane. For such purpose, five families of full-sibs were evaluated, each with 360 individuals, in the randomized blocks design, with three replications in three different spacing among plants in the row (50 cm, 75 cm, and 100 cm) and 150 cm between the rows. To determine the ideal sample size, as well as the better spacing for evaluation, the bootstrap method was adopted. It was observed that 100 cm spacings provided the best average for the stalk numbers, stalk diameter and for estimated weight of stalks in the stool. The spacing of 75 cm between the plants allowed a better power of discrimination among the families for all characters evaluated. At this 75 cm spacing was also possible to identify superior families with a sample of 30 plants each plot and 3 reps in the trial. Highlights The bootstrap method was efficient to determine the ideal sample size, as well as the best spacing for evaluation. The 75-cm spacing had the highest power of discrimination among families, indicating that this spacing is the most efficient in evaluating sugarcane families for selection purposes. From all the results and considering selective accuracy as the guiding parameter for decision making, the highest values obtained considering the number of stalks and weight of stalks in the stools were found at the 75-cm spacing.

Performance of vermicomposted wastes for tomato (Lycopersicon Esculentum Mill.), production: A case study of Embu, Kenya

Purpose To investigate the effect of vermicomposted kitchen, market and tea wastes on tomato growth and yield and assess the benefits and costs that arise.Method A field experiment arranged in the randomized complete block design with five experimental treatments: vermicomposted kitchen, market, tea wastes, NPK fertilizer and a control, replicated thrice was conducted. Data were collected on plant height, number of leaves, number of branches, number of flower stalks, fruit number, fruit weight, above-ground biomass, marketable tomato yield, soil nutrient content, pH, texture and exchangeable acidity. Data obtained were analyzed using SAS version 9.4 by subjecting to one-way Analysis of Variance (ANOVA). Biophysical crop data means were separated using Tukey’s Studentized Range (HSD) test at p=0.05 significance level. T-test was used to determine the difference in soil nutrient content (Nitrogen (N), Phosphorus (P), Potassium (K), Carbon (C)) at the beginning and end of the study. The benefits and costs were analyzed using the benefit-cost ratio formula.Results The three vermicomposts had a similar effect (p>0.05) in influencing most of the tomato crop variables such as plant height, leaves number, branch number and flower stalks number. Tea waste vermicompost and kitchen waste vermicompost gave significantly high tomato yields of 115 t ha-1 and 113 t ha-1 at p=0.0001 as well as the highest benefit-cost ratio of 1.4:1.Conclusion Tea, market and kitchen wastes have a potential for use in the production of high-quality vermicompost that can be used as a soil amendment to enhance tomato performance.

Investigating the relationships between soil and sugarcane attributes under different row spacing configurations and crop cycles using the state-space approach

The adoption of different row spacing configurations has been advocated as a possible solution to mitigate the problems related to soil compaction in sugarcane areas due to the frequent use of heavy agricultural machines. This study aimed to (i) identify factors that influence the relationships of biometric attributes of sugarcane and attributes of an Oxisol soil under different scenarios in Southern Brazil and (ii) describe the distribution of the biometric attributes of sugarcane through state-space analysis under all the evaluated scenarios. Sugarcane was planted using conventional planting systems. The total experimental area of 200 m × 20 m consisted of three row spacing configurations: (i) single-row spacing; (ii) double-row spacing; and (iii) triple-row spacing. In each row spacing configuration, a transect was established, and fifty soil sampling points were distributed at equal distances. At each point and transect, disturbed and undisturbed soil samples were collected in the 0.00–0.10 m soil layer to determine soil bulk density, total porosity, macro- and – microporosity, soil penetration resistance and water content at field capacity in three sugarcane crop cycles. At the end of each crop cycle and each transect, stalk height, number of stalks per square meter, stalk mass and tons of stalks per hectare were determined at each sampling point. All the data sets were analyzed using descriptive statistics and ANOVA. In addition, using the Tukey test, the mean values of each attribute were compared to assess the effects of each row spacing configuration and sugarcane crop cycle on all the soil and crop attributes. Spatial relationships of the biometric attributes of sugarcane and co-regionalized soil attributes under each row spacing and crop cycle were evaluated using the auto- and cross-correlation functions and the state-space approach. There were no statistically significant differences between the crop and soil attributes measured under the single- and double-row spacing configurations. In addition, it is expected that with the advance in the age of the sugarcane crop, a superiority of the performance of the double-row spacing, compared with the single-row spacing, will be observed, due to the possibility of monitoring the traffic control under the double-row spacing configuration. On the other hand, the adoption of the triple-row spacing configuration caused negative effects on all the crop and soil attributes, compared with the other two row spacing configurations. Future studies of sugarcane crop and soil attributes should be developed to validate the state-space approach in other environmental conditions.

Research on rheological property of hydrochar based bio modified asphalt binder: A promising way to solve environmental problems caused by waste corn stalks

A large number of corn stalks are produced with the development of agriculture, while the inappropriate disposal will cause serious problems to the environment. However, limited researches are available which investigate the feasibility of applying corn stalks in asphalt. The main goal of this research is to explore the possibility of using Hydrochar(HC) from corn stalks as a novel asphalt modifier. In this study, HC was produced from corn stalks by a new method called hydrothermal carbonization. The comprehensive rheological properties of Hydrochar modified asphalt(HCMA) with different HC dosages were investigated by Bending beam rheometer (BBR) and Dynamic shear rheometer (DSR). Moreover, storage stability of HCMA was also explored. The experimental results demonstrated that the HC modifier was able to enhance the rutting resistance of base asphalt. The fatigue performance of base asphalt was improved by HC. Furthermore, rutting resistance showed an upward trend and fatigue performance showed a downward trend with the increasing of HC content. However, the addition of HC adversely affected the low temperature cracking resistance of base asphalt. Besides, the storage ability of HCMA should be improved. Finally, it is believed that the application of HC from corn stalks as asphalt modifier in warm regions is a promising way to reduce environmental pollution and hydrothermal carbonization is a promising approach to solve environmental problems caused by corn stalks.

Nitrogen and calcium fertilization on the growth and development of gerbera cultivated in pots for cut flowers

ABSTRACT Gerbera is a flowering species with relevance to the cut flower market. Understanding nutritional requirements of the species is important to improve fertilization procedures. In the present work, our objective was to evaluate the influence of different doses of nitrogen (N) and calcium (Ca) on the growth and development of gerbera cultivated in pots as a cut flower. The experiment was conducted in a protected environment in a bifactorial design, with an additional treatment consisting of the combination of three N (0.07, 0.15 and 0.2 g L-1 substrate) and Ca (0.02, 0.03 and 0.04 g L-1 substrate) doses applied every 15 days. Control plants were not supplemented with either N or Ca. No significant interaction between N and Ca doses was observed. The highest number of flower stalks was obtained with 0.15 g N L-1 substrate and 0.04 g Ca L-1 substrate. Flower diameter, plant leaf area and total chlorophyll contents were at a maximum of 0.14 g N L-1 substrate and 0.04 g Ca L-1 substrate. N and Ca doses influenced in an independent manner the growth and development of gerberas as a cut flower cultivated in pots, and we determined that its fertilization should occur every 15 days with 0.34 g N L-1 substrate and 0.04 g Ca L-1 substrate.

Growth and Results of Three Varieties Celery (Apium graveolens L) With Addition of Alternative Nutrition in the Hydroponic Floating System

The objectives of the research were to determine the best varieties of celery and nutrient concentration with the addition of azolla extract for growth and yield of celery, and obtaining the best combination of varieties and nutrient concentrations for growth and yield of celery in the hydroponic floating system. The research was conducted at Screen house number A. 24 and the Laboratory of Agronomy and Horticulture, Faculty of Agriculture, Jenderal Soedirman University and was conducted from January 2020 to April 2020. The research was arranged in a two-factorial randomized block design. The first factors were varieties treatment (V): V1 (Summer variety), V2 (Amigo variety), V3 (Tall Utah variety). The second factors were treatment of nutrient concentration (K): K1 (AB mix solution 900 ppm + azolla extract 60 ml / l), K2 (AB mix solution 1100 ppm + azolla extract 60 ml / l), K3 (AB mix solution 1300 ppm + azolla extract 60 ml / l), K4 (AB mix solution 1500 ppm without azolla extract). The research variables observed were plant height, number of leaves, amount of chlorophyll, fresh root weight, dry root weight, fresh shoot weight, dry shoot weight, root length and number of stalks. The results showed that the Tall Utah variety and the nutrient concentration of 1300 ppm + 60 ml / l azolla extract was the best treatment for growth and yield of celery. The interaction between the two treatments of Tall Utah varieties and nutrient concentrations of 1300 ppm + azolla extract 60ml / l showed the best treatment on the variable number of leaves 39.16, total chlorophyll 49.91, fresh root weight 7.57 g, dry root weight 0, 73 g, dry shoot weight 2.11 g, root length 9.11 cm, and the number of petioles 8.94 pieces.

Initiation of Flowering and Bulbils in Shallot with Various Treatments in Tropical Regions

Background: Shallots are one of the horticultural commodities with low production growth value in Indonesia. Shallots production in Indonesia is limited by the quality of planting material and the climate, especially temperature. The flowering of shallots is a significant obstacle to the regulation of tuber development and bulbils. This study aimed to examine the effect of treatment on the initiation of flowering and the formation of bulbils. Methods: The method used was a complete randomized block design with six treatments: without treatment, vernalization at 5oC, Immersion GA3 100 ppm, Immersion IAA 100 ppm, Immersion NAA 100 ppm, injury to the flower stalk and three replications. Result: The treatment of flowering initiation and the formation of bulbils had a significant effect on the flowering day, the number of flower stalks, the percentage of flowering plants, number weight of bulbils and weight of bulbils. GA3 and vernalization can speed up the appearance of flowers and increase the percentage of flowering plants. GA3 and the opening of the flower stalks can encourage the formation of bulbils with a higher weight and diameter of the tubers. The flowering day had a negative correlation with the number of bulbils formed. Bulbils formation requires a higher content of endogenous GA3. GA3 can initiate the flowering and formation of shallot bulbils.

Foliar application of micronutrients enhances growth, flowering, minerals absorption and postharvest life of tuberose (Polianthes tuberosa L.) in calcareous soil

Micronutrients applications are effective for better crop production in calcareous soils because these soils are usually deficit in iron (Fe), zinc (Zn) and boron (B). In Pakistan, most of soils are calcareous in nature. When tuberose is grown in such soils as a cut flower, its production is negatively affected. Therefore, a study was aimed to evaluate the effects of micronutrients as foliar sprays on cut tuberose production in calcareous soil. Micronutrients (Fe, Zn and B) alone and in combinations were sprayed on the plants after 60, 90 and 120 days of planting. The mixture of all these three micronutrients increased the plant height (95.77 cm), chlorophyll content (38.13 SPAD), number of leaves (79.63), leaf length (44.73 cm), fresh (111.64 g) and dry (16.16 g) plant weights, root length (15.13 cm), number of stalks (3.73), stalk length (79.03 cm), spike length (22 cm), number of florets (51.67), floret fresh weight (11.85 g), leaf Zn concentration (53.6 mg/g) and vase life (8.4 days). Fe + Zn enhanced the number of leaves (76.60), leaf length (45.83 cm), root length (15.05 cm), spike length (22.33 cm), and leaf Fe (128.18 mg/g) and Zn concentrations (55.02 mg/g). The Fe spray increased the leaf length (44.10 cm), days to flower initiation (142.47 days) and leaf Fe concentration (130.75 mg/g) in tuberose plants. Application of Zn improved the leaf length (45.87 cm) and diameter (1.32 cm), root (15.03 cm), spike (21.77 cm) and floret lengths (4.74 cm), floret dry weight (1.49 g) and leaf Zn concentration (57.5 mg/g). Foliar spray of B increased the B concentration (21.1 mg/g) in tuberose leaves. It is concluded that foliar application of micronutrients alone and in combinations improved the plant growth, flowering, leaf minerals concentrations and vase life of tuberose spikes. However, mixture of Fe, Zn and B was more effective as compared to other treatments. Moreover, current study encourages the foliar application of micronutrients in tuberose when grown in calcareous soils.

EFFECTS OF DIFFERENT WATER STRESS LEVELS ON BIOMASS YIELD AND AGRONOMIC TRAITS OF SWITCHGRASS (Panicum virgatum L.) CULTIVARS UNDER ARID AND SEMI-ARID CONDITIONS

This study was conducted to determine the effects of different water stress levels on biomass yield, plant height, number of stalks per unit area, single stalk weight, yield reduction ratios and irrigation water use efficiency (IWUE) values of switchgrass (Panicum virgatum L.) cultivars under Central Anatolia conditions. Experiments were conducted for two years (2016 – 2017) in randomized blocks – split plots experimental design with three replications under Konya ecological conditions. Six switchgrass cultivars (Shelter, Alamo, Cave in rock, Shawnee, Kanlow and Trailblazer) and five different irrigation treatments (water stress levels: S1: Full irrigation; S2: 75% of full irrigation; S3: 50% of full irrigation; S4: 25% of full irrigation and S5: Rain-fed without irrigation) were used in present experiments. Kanlow, Alamo and Trailblazer cultivars had greater biomass yields than the other cultivars in all water stress treatments. Under different water stress treatments, dry biomass yields varied between 48300 kg ha-1 (S5- Cave in rock) and 25120 kg ha-1 (S1- Kanlow); plant heights varied between 70 cm (S5) and 180 cm (S1); number of stalks per unit area (meter) varied between 221 (S5) and 356 (S1); stalk weights varied between 0.56 g (S5) and 2.25 g (S1). IWUE was calculated as 5.7 kg m-3 for the first harvest and as 2.1 kg m-3 for the second harvest. Considering the biomass yields from single harvest of rain-fed treatments (S5) and two harvests of the other irrigation treatments (S1-S4), IWUE values and water deficits of the region, it was concluded that single harvest was more suitable for switchgrass plants grown under ecological conditions

Biomass yield, dry matter partitioning and physiology of commercial and Erianthus introgressed sugarcane clones under contrasting water regimes

The productivity of sugarcane is limited by several biotic and abiotic stresses, of which drought is an important environmental stress, causing substantial yield losses especially in tropical parts of the world. The present day sugarcane cultivars are derivatives of interspecific hybrids involving Saccharum officinarum and S. spontaneum and the drought tolerance is governed by S. sponaneum. Of late considerable attention has been given to utilize Erianthus Spp, the related wild genera of Saccharum, shows remarkable levels of drought tolerance under water limited condition. In this study, experiments were conducted to compare the influence of drought on biomass, yield and physiology of commercial and Erianthus introgressed clones. The results showed that the cane yield was reduced 37.98% in commercial clones compared to 24.67% in Erianthus introgressed clones under drought. The highest stress tolerance index (STI) of 1.256 was recorded in the clone CYM 08–922 which is a backcross hybrid involving Erianthus arundinaceus. Significant differences were observed for leaf area index, relative water content, lipid peroxidation and epicuticular wax content among the genotypes and between treatments. Sugar yield was most affected by drought (38.86%) followed by cane yield (33.30%), NMC (26.79%) and single cane weight (22.49%). Cane yield showed a positive and significant correlation with dry biomass under both irrigated (r = 0.303) and drought situations (r = 0.404) and among the physiological parameters, only RWC showed significant and positive correlation with cane yield (r = 0.307). The leaf dry matter was 14.55% higher under drought indicating influence of drought on translocation of dry matter from leaves to canes. Among clones CoM 0265, Co 06022, CYM 08-922, CYM 09-1369 and GU 12-31 showed greater ability to partition dry matter in to canes under drought than the other clones and had higher stress tolerant index. Cane height, number of millable stalks and RWC% showed positive and significant association with cane yield under both drought and irrigated condition and could be important parameters in screening clones under sugarcane improvement programmes.

Genetic Variability, Correlation among Agronomic Traits, and Genetic Progress in a Sugarcane Diversity Panel

Sugarcane breeding programs require 15 years of experimentation to create more productive cultivars, and estimates of genetic progress can indicate the efficiency of breeding programs. In this study, we used a diversity panel, the Brazilian Panel of Sugarcane Genotypes (BPSG), with the following objectives: (i) to estimate, through a mixed model, the adjusted means and genetic parameters of ten traits evaluated over three harvest years; (ii) to estimate genotypic correlation among those traits; and (iii) to estimate genetic progress over six decades of breeding. The heritabilities ranged from 0.43 to 0.88, and we detected 42 significant correlations, 9 negative and 33 positive. Over six decades, the sucrose-related traits BRIX, POL%C, and POL%J showed an average increase per decade of 0.27 °Brix, 0.26% and 0.31%, respectively. Stalk number, height, and weight of the plot, and cane and sucrose yields revealed average increases per decade of 3.27 stalks, 0.06 m, 9.42 kg, 11.22 t/ha, and 2.08 t/ha, respectively. The genetic progress of the main agronomic traits is discussed through a historical series of sugarcane genotypes present in the BPSG. The findings of this study could contribute to the management of new breeding strategies and allow for future studies of associative mapping.

Development and diversity analysis of an hexaploid pre-breeding asparagus population with introgressions from wild relative species

The development of new asparagus (Asparagus officinalis L.) cultivars has been hindered by the lack of genetic diversity in the crop. The current study aims at generating novel plant material to widen the genetic base of the crop by using CWR (crop wild relatives). We have developed a hexaploid population of about 1000 plants with introgressions of four polyploid CWR species (A. maritimus, A. pseudoscaber, A. brachyphyllus and A. macrorrhizus). The population is the second generation from a first backcrossing using the landrace ‘Morado de Huétor’ as recurrent parent and was obtained in open pollination. The diversity of the population was analyzed by six EST-SSR (Expressed Sequence Tag-Simple Sequence Repeat) markers. A random sampling of 60 plants was used to estimate the genetic variability. The results were compared with data previously obtained from the parental collection, the landrace ‘Morado de Huétor’ and diploid current asparagus cultivars. The average PICm (polymorphic information content) value of the new population and ‘Morado de Huétor’ were similar (>0.8) and higher than the value observed in the diploid cultivars (0.61). At least 22.2% of the alleles detected in the hexaploid population were specific from the CWR species used in this study. Principal coordinate analyses (PCoA) revealed a clear genetic diversity differentiation between populations. The population of 1000 plants was evaluated for agronomic traits (earliness, stalk number, branching height and stalk thickness) for two years and we selected 80 plants to develop a breeding base population. Variation was significant for all traits (P<0.001). These 80 plants were also analyzed with the six EST-SSR markers and they conserve the variability present in the starting population. The results show an increase in the genetic variability and offer a new opportunity for asparagus improvement.

Response of Chosen American Asparagus officinalis L. Cultivars to Drip Irrigation on the Sandy Soil in Central Europe: Growth, Yield, and Water Productivity

The aim of this study was to verify the response of 13 American asparagus cultivars cultivated for green spear on surface postharvest drip irrigation. Irrigation, used to compensate for periodic deficiencies in precipitation, allows for high- and good-quality crops for many species. The field experiment was carried out in 2006–2008 on a very light sandy soil in central Europe (Poland). Irrigation treatments were applied using the tensiometer indications. Water requirements of asparagus were calculated on the base of reference evapotranspiration and crop coefficients. The following evaluations were made: Height, diameter, and number of summer stalks, as well marketable yield, weight, and number of consumption green spears. Drip irrigation applied for 2 years (2006–2007) in the postharvest period had a positive effect on all studied traits in both summer stalks and green spears in 2007–2008. A significant increase in the height, number, and diameter of summer stalks, as well an increase in the marketable yield, weight, and number of green spears was observed for most of the cultivars. In general, postharvest drip irrigation of asparagus cultivated in very light sandy soil significantly contributes to the increase in productivity of American cultivars of this species.

PRODUCTIVITY OF STRAWBERRY VARIETIES IN THE CONDITIONS OF THE REPUBLIC OF BASHKORTOSTAN

The article presents the results of research on the study of varieties of garden strawberries. The article presents the results of research on biometric records for varieties of garden strawberries of the first and second year of cultivation in the conditions of the southern forest-steppe of the Republic of Bashkortostan. The number of flower stalks, fruits, potential productivity were studied and the results of the yield of the cultivated plants were obtained. Of the studied varieties, the most productive were the Kimberly and Clery varieties with a berry yield of 18.9 and 15.9 t / ha.

Sugarcane growth and yields in response to long-term monoculture practices under different soil orders

Indonesia is the seventh largest sugar producer in the world. Monoculture sugarcane cultivation has been practiced since the Dutch era, especially in the Entisols, Inceptisols and Vertisols soil orders. The field research with this multilocation design aims to determine the effect of the monoculture sugarcane cultivation period (1–10, 11–20 and 21–30 years) on the growth and yield of sugarcane plants under the three soil orders. Analysis of variance (ANOVA) at a 5% significance and correlation was conducted to determine the effects of soil orders and monoculture period. The results showed that there were significant interactions between monoculture period and soil order on leaf fresh weight, leaf dry weight, root fresh weight, plant height, stalk diameters, number of stalks, leaf area, number of green leaf, root CEC, root length, root surface and root area. There was no interaction between monoculture period and soil order on stalk fresh weight, stalk dry weight, root dry weight, number of nodes. The sucrose content of sugarcane in Entisols at the 1–10 years monoculture period significantly lower (6.03%) compared to 11–20 years period (7.37%) and 21–30 year (7.79%), whereas at the 1–10 years monoculture period in Inceptisols and Vertisols (7.99% and 8.04 %) was significantly higher than that of Entisols (6.03%). Sugarcane productivity at monoculture period 1–10 years in Entisols significantly lowest (49.38 t/ha) compared to Inceptisols (54.82 t/ha) and Vertisols (63.05 t/ha) at the same period, while the 21–30 years period on Vertisols significantly highest (76.18 t/ha) compared to 11–20 years period (68.73 t/ha) and 1–10 years period (63.05 t/ha) in same soil order. These conditions indicate that the effect of long-term monoculture cultivation of sugarcane on the growth and yield of sugarcane varies, depending on the soil order as the grow medium and root parameters have the highest correlation with sugarcane yield. Land management to improve the root area is necessary for optimal plant growth.

Characterization of Conserved Sugarcane (&lt;em&gt;Saccharum&lt;/em&gt; spp.) Germplasm for Parental Selection in Directional Breeding of Economically Important Traits

Enhancement of sugar production in Sri Lanka is very important since a large amount of foreign exchange is spent on sugar importation every year. Cultivation of improved varieties developed through proven crosses involving selected parents, for desired cane and sugar yield components, is a necessity to reach the production targets in Sri Lanka. The present study focused on the evaluation of 509 sugarcane parental accessions (<em>Saccharum </em>spp.) for important cane and sugar yield traits. Twelve different cane and sugar yield components; plot weight, stalk length, stalk diameter, number of stalk per plots, hand refractometer brix, rind hardness, laboratory brix, pol in juice, purity, pure obtainable cane sugar, fibre percent fresh weight and sugar yield per plot were measured or estimated. The data were statistically analyzed for testing significance of variance ratios (ANOVA), phenotypic correlations, clustering of parental clones and estimation of breeding values of the parental clones. The results revealed stalk length and number of stalks to be the major determinants of cane yield. A total of 2,500 bi-parental crossing combinations were identified from the selected parental accessions with the best breeding values for the development of high cane and high sugar yielding progenies. The accessions H 820778, M 1356, SL 89 2688, SLC 87 04, SLC 08 62, SLC 08 106, SLC 12 05 and SLC 91 20 were identified as the most promising parents to be used in simultaneous improvement of cane yield and sugar content with moderate fibre content.

Data mining sugarcane breeding yield data for ratoon yield prediction

Ratooning ability is important for sugarcane (Saccharum spp.), but due to time constraints relevant third ratoon yield data is not gathered before breeding selections are made. If third ratoon could be predicted, selections would improve. Machine learning (ML) techniques utilize yield variables to create predictors. Yield variables from 11 locations, 24 genotypes, and 20 cycles were used in a model to predict third ratoon-cane yield cross validated by cycle using ML and statistical techniques including Linear Regression, Random Forest, AdaBoost, Stochastic Gradient, Neural Network, Support Vector Machines, and k-nearest neighbors algorithm. Prediction error was measured as the difference between predicted and measured third ratoon cane yield. A model that partitioned overall prediction error into sources of variances indicated that location within cycle (52%) followed by genotype by location within cycle (10%) were the largest sources of error for predicting ratooning ability. Ratoon stalk number, sucrose and cane yield ranked highly toward predictions. The Adaboost (AB) ML predictors of third ratoon cane yield had lower experimental error, when compared to second ratoon as a third ratoon predictor. However, prediction by cycle was not consistently lower than second ratoon as a predictor. If unique locations were removed, then AB predictions had less error and better predictors of third ratoon than second ratoon in 75% of the cycles tested, thus demonstrating the potential and limitations of utilizing harvest and location data for ML predictions.