Arachis Pintoi Research Articles

Light competition is the key factor determining spatio-temporal variability in legume proportion within Marandu palisadegrass–forage peanut mixed pastures

Context Understanding ecology in grass–legume pastures can help support strategies aimed at maintaining canopy stability in terms of botanical composition. Aims This 2-year study evaluated spatial variability, focusing on plant structural characteristics in a Marandu palisadegrass [Urochloa brizantha (Hochst. Ex A. Rich.) R.D. Webster cv. Marandu]–forage peanut (Arachis pintoi Krapov. and W.C. Greg. cv. BRS Mandobi) mixed canopy under grazing in continuous stocking management. Methods The pasture was managed with canopy height of 20–25 cm. The experimental area had a permanent sample grid containing 50 pre-established and georeferenced plots. Principal component analysis was performed, and spatial dependence structure of the first principal component and structural variables were separately characterised by geostatistical analysis. Key results There was spatial dependence of the structural characteristics, with marked spatial heterogeneity in the distribution of all variables. Taller grass canopies caused competition for light between species, reducing legume contribution and inducing more erect forage peanut growth habit. Conversely, in areas with lower grass canopy height, forage peanut botanical composition increased to up to 70%, as it propagated more effectively by stoloniferous propagation. Conclusions The canopy structure spatial variability of a Marandu palisadegrass–forage peanut mixed pasture determines the overall average pasture grass/legume proportion. In regions with taller canopies, Marandu palisadegrass was favoured, while in areas with shorter canopy, forage peanut proportion was promoted. Satisfactory legume proportions can be reached in the canopy despite areas with reduced legume contribution. Implications Our findings using geostatistical techniques facilitate the development of useful and innovative tools allowing better comprehension for the management of mixed pastures.

Highlighting the benefits of biological nitrogen fixation on agronomic, physiological, and nutritive value traits of brachiariagrass

The search for efficiency in forage-based systems has intensified in recent years, increasing the need to reduce environmental impacts of animal agriculture. Reducing the dependence on fossil fuels for nitrogen (N) input with the use of microorganisms (e.g., biological nitrogen fixation, BNF) and grass-legume mixed stands has become an important practice. The objective of this study was to evaluate N input strategies that affect the agronomic, physiological, and nutritive value traits of Ipyporã brachiariagrass (Brachiaria hybrid ‘BRS RB331 Ipyporã’) based on the use of mineral N fertilization (ammonium sulfate), bacterial inoculation (Azospirillum brasilense strains Ab-V5 and Ab-V6; CNPSo), and mixed stands with forage peanut (Arachis pintoi Krapov. & W.C. Greg. cv. BRS Mandobi) in the Amazon biome. The treatments were six N-input strategies: 1. pastures with no nitrogen fertilization (control); 2. fertilized with 80 kg N ha-1 season-1 (N); 3. inoculated with A. brasilense (Az); 4. fertilized with 80 kg N ha-1 season-1 + A. brasilense (N + Az); 5. mixed stand of Ipyporã brachiariagrass and forage peanut (Mix) and 6. mixed stand + A. brasilense (Mix+Az). The experimental period was from 20 January 2015–21 March 2017, covering three summer growing seasons. Forage was cut to a 12-cm stubble when average canopy height reached 25 cm. Annual forage accumulation (FA) was greater in N, Az, N + Az, and Mix+Az (averaged 7760 kg DM ha-1) than in Control and Mix (averaged 6485 kg DM ha-1). The FA measured in Az and Mix+Az was equivalent to applying 58 and 86 kg of N ha-1, respectively when compared with Control. The greatest leaf mass was measured in N, Az, N + Az, and Mix+Az (averaged 1475 kg DM ha-1). The Az and Mix+Az can be options to improve the sustainability of forage systems and maintain forage production while using renewable sources for nitrogen.

Impact of cover crop and mulching on soil physical properties and soil nutrients in a citrus orchard.

BackgroundCover crops and mulching can ameliorate soil porosity and nutrient availability, but their effects on the physical characteristics and nutrients in the raised bed soils are unclear.MethodsThe field experiment was conducted in a pomelo orchard from 2019 to 2021, with an area of 1,500 m2. The treatments included control (no cover crop), non-legume cover crop (Commelina communis L.), legume cover crop (Arachis pintoi Krabov & W.C. Gregory), and rice straw mulching (Oryza sativa L.). At the end of each year (2019, 2020, and 2021), soil samples were collected at four different layers (0–10, 10–20, 20–30, and 30–40 cm) in each treatment. Soil bulk density, soil porosity, and the concentration of nutrients in the soil were investigated.ResultsThe results revealed that soil bulk density at two depths, 0–10 and 10–20 cm, was reduced by 0.07 and 0.08 g cm−3 by rice straw mulch and a leguminous cover crop, thus, increasing soil porosity by ~2.74% and ~3.01%, respectively. Soil nutrients (Ca, K, Fe, and Zn) at topsoil (0–10 cm) and subsoil (10–20 cm) layers were not significantly different in the first year, but those nutrients (Ca, K, Fe, and Zn) improved greatly in the second and third years.ConclusionsLegume cover crops and straw mulch enhanced soil porosity and plant nutrient availability (Ca, K, Fe, and Zn). These conservation practices best benefit fruit orchards cultivated in the raised bed soils.

Description of Porphyrosela arachisella sp. nov. (Lepidoptera: Gracillariidae), the first report of Lithocolletinae for Brazil

During a recent survey of leaf-mining microlepidoptera in the Cerrado biome, mines of an undescribed Porphyrosela Braun (Lepidoptera: Gracillariidae: Lithocolletinae) were found associated with the forage peanut, Arachis pintoi Krapov. W.C. Greg. (Fabaceae). Consequently, adults, immature stages and the leaf mine of Porphyrosela arachisella sp. nov. are herein described based on light and scanning electron microscopy. A preliminary analysis of DNA barcode sequences including putative members of other lithocolletine species and all BINs (Barcode Index Numbers) available for Porphyrosela supports P. arachisella as an independent cluster, with 8 to 11% divergence. Its nearest neighbour was the cluster formed by three BINs (BOLD: ADT2137, BOLD: AAG1161 and BOLD: ADU9985) that includes specimens from Australia, Vietnam and Bangladesh. This is the first report of a lithocolletine gracillariid for Brazil, and the third species recognized for the genus in the Neotropical region.

Effects of lactic acid bacteria with bacteriocinogenic potential on the chemical composition and fermentation profile of forage peanut (Arachis pintoi) silage

The objectives of this study were to evaluate the effect of lactic acid bacteria (LAB) with bacteriocinogenic activity isolated from stylo silages on the microbial population, chemical composition and fermentation profile of forage peanut silage (FPS) and to identify LAB species in forage peanut and its silages based on the 16 S rRNA sequence analysis. The experiment was conducted in a completely randomized design with a 5 × 6 factorial arrangement (five inoculants (I) × six fermentation periods (P)) and three replicates. The following inoculants were evaluated: without inoculant (CTRL); a commercial inoculant at a dose of 107 colony forming units (cfu) g-1 fresh matter (CI1); a commercial inoculant at a dose of 105 cfu g-1 fresh matter (CI2); Pediococcus acidilactici strain 10.6 (S1); and Pool of bacteriocinogenic strains (POOL), including S1, P. pentosaceus strain 6.16 and P. acidilactici strain 10.4. The fermentation periods were 1, 3, 7, 14, 28 and 56 days. The largest LAB populations were observed in silages treated with S1 (8.66 log cfu g-1) and POOL (8.69 log cfu g-1). At the end of the fermentation period, a higher content of dry matter (222.53 g kg-1) and lactic acid (66.30 g kg-1) and lower values of pH (4.76) and acid detergent insoluble nitrogen (9.50% of total nitrogen) were observed for silage treated with S1. The screening of LAB from forage peanut silage revealed that P. pentosaceus was the predominant species. In addition, the wild strain of P. acidilactici 10.6 established a desirable microbial population during the fermentation process reflecting a highest lactic acid concentration and lowest pH values after 56 days of fermentation.

Intercropping Pinto Peanut in Litchi Orchard Effectively Improved Soil Available Potassium Content, Optimized Soil Bacterial Community Structure, and Advanced Bacterial Community Diversity

Intercropping is widely used in agricultural production due to its capability of raising land productivity and providing an opportunity to achieve sustainable intensification of agriculture. In this study, soil samples from 10 to 20 cm depth of intercropping Pinto peanut in litchi orchard and litchi monoculture mode were established to determine soil attributes, enzyme activities, as well as the effect on soil bacterial diversity. On this basis, 16S rRNA V4-V5 region of soil bacterial communities in litchi/Pinto peanut intercropping (LP) mode and litchi monoculture mode (CK) was detected by the Illumina MiSeq sequencing platform. The results showed that the content of available potassium (AK) in LP was significantly higher than that in CK by 138.9%, and the content of available nitrogen (AN) in LP was significantly lower than that in CK by 19.6%. The soil enzyme activities were higher in LP as a whole, especially sucrase (SC) and acid protease (PT) were significantly higher by 154.4 and 76.5%, respectively. The absolute abundance and alpha diversity of soil microbiota were significantly higher in the intercropping group. Most importantly, endemic species with a significant difference in LP was higher by ~60 times compared to CK treatment. In the aspect of soil bacterial community structure, the dominant phyla of the two groups were Acidobacteria, Proteobacteria, Chloroflexi, and Actinobacteria. At the genus level, the absolute abundance of Flavobacterium and Nitrososphaera was significantly higher by 79.20 and 72.93%, respectively, while that of Candidatus_Koribacter was significantly lower with an amplitude of 62.24% in LP than in CK. Furthermore, the redundancy analysis (RDA) suggested that AK, which was highly associated with the dominant genera and phyla, is the vitally dominating environmental factors in LP groups, while in CK groups, it is AN and pH. In addition, PICRUSt2 analysis indicated that intercropping improved the metabolic activity of bacteria which can be correlated to the resistance of litchi root systems to soil-borne diseases. Overall, this study is expected to provide a theoretical basis and technical support for the healthy intercropping cultivation of litchi.

Diversity of Spider Mites (Tetranychidae) on Ornamental Plants in Central Kerala

Purposive sampling surveys were conducted in homestead gardens and ornamental nurseries at different localities of Thrissur and Ernakulam districts during 2017-19 to study the diversity of spider mites associated with ornamental plants. Mite samples collected from rose, adenium, gerbera, marigold, chrysanthemum, balsam, cock’s comb, orchid, cassia, cairo morning glory, zinnia, bauhinia, crape jasmine and pinto peanut were maintained as isoline cultures in the laboratory. Male and female specimens from isolines were slide mounted for morphological characterisation and identification. The results revealed eight species belonging to three genera viz., Tetranychus truncatus Ehara, T. okinawanus Ehara, T. urticae Koch, T. fijiensis Hirst, T. neocaledonicus Andre, T. marianae McGregor, Eutetranychus orientalis Klein and Oligonychus biharensis Hirst. The study recorded new hosts for the alien species, T. okinawanus and T. truncatus which suggests the potential of these species to turn invasive in Kerala’s ecosystems. The spider mite fauna on rose was more diverse, indicating the need for imposing strict quarantine regulations. The study observed T. marianae as a new record from Kerala.

Can application of organic matter, cover crops and tree planting improve infiltration rate of soil covered by pyroclastic materials?

Pyroclastic materials from volcanic eruption is easily compacted and may develop surface crust, which potentially decreases water infiltration. We conducted research in Ngantang, regularly affected by Mt. Kelud eruption, as an attempt to improve water infiltration using organic matter and cover crop. The organic matter (20 Mg.ha-1) used was sweet potato leaves (Bsp) and Tithonia diversifolia leaves (Btd). Cover crops (Arachis pintoi (Tap) and Tithonia diversifolia (Ttd)) and tree (Paraserianthes falcataria (P1)) were planted. Ring infiltrometer was used to measure infiltration rate on initial soil, on soils covered by pyroclastics after 3 months organic matter and cover crops application, and after one year tree planting. The result showed that infiltration rate of initial soil was significantly decreased with time, when covered by eruption materials. After 3 months application of organic matter and cover crops, infiltration rate was significantly higher than untreated soil covered by volcanic materials. Planting tree increased infiltration rate with the highest infiltration rate occurred in combination with organic matter Tithonia diversifolia leaves and Tithonia diversifolia cover crops. Infiltration rate increased with increasing total pores, but decreased with increasing of meso-pores, especially 12 months after application organic matter, together with planting cover crops and tree.

Effectivity of several types of placemat application on pinto peanut (Arachis pintoi Krap. & Greg.) growth and pols harvesting

Effectivity of several types of placemat application on pinto peanut (<i>Arachis pintoi</i> Krap. &amp; Greg.) growth and pols harvesting

Effectivity of pinto peanut (Arachis pintoi Krap. &amp; Greg.) propagation material to soil surface covering rate

Effectivity of pinto peanut (<i>Arachis pintoi</i> Krap. &amp; Greg.) propagation material to soil surface covering rate

Biological test of compost made of rabbit faeces and the addition of banana peels on the vegetative growth of Morus alba and Arachis pintoi

The purpose of this research was to determine vegetative growth performance of Morus alba and Arachis pintoi with different percentages of compost mixture (rabbit feces and kepok banana (Musa paradisiaca Linn) peels) and soil as media. The materials used was 72 Morus alba stacks, rabbit faeces, kepok banana peels, and Azotobacter culture as decomposer. This research was conducted by Completely Randomized Design with 4 treatments and 6 replications. The treatments were T0 (100% soil), T1 (20% of compost and 80% of soil), T2 (40% of compost and 60% of soil), and T3 (60% of compost and 40% of soil). The data was analysed using analysis of variance, followed by Duncan’s Multiple Range Test (DMRT) if the results are significantly different. The treatment gave higher leaves number, roots weight, and roots length (P&lt;0.05) in Morus alba. Same also on plant length, branches number and wet weight (P&lt;0.05) of Arachis pintoi. The conclusion of this research is that the application of organic compost based on rabbit manure and banana peel with Azotobacter microbial culture decomposer can improve the growth performance of Morus alba and Arachis pintoi. The best level was T1 with 20% of compost and 80% of soil.

Silagens mistas de cana-de-açúcar e amendoim forrageiro tratadas com Lactobacillus buchneri

Abstract There is evidence for the beneficial effects of forage peanut on the nutritive value and fermentation profile of silages; however, its effects on sugarcane silage have not been determined. The objective of the study was to evaluate the chemical composition, fermentation profile, microbial composition, and dry matter recovery (DMR) of sugarcane silage containing various amounts of forage peanut (Arachis pintoi cv. Belmonte) (0%, 25%, 50%, and 75% on a fresh matter basis), treated or untreated with Lactobacillus buchneri. A completely randomized 4 × 2 factorial design was used with three replications. The interaction between forage peanut levels and inoculant influenced the concentrations of dry matter, crude protein, neutral detergent fiber and acid detergent fiber, organic acids and ethanol, populations of lactic acid bacteria and yeast, gas and effluent losses, and DMR. Forage peanut levels had effects on dry matter, hemicellulose, acid detergent insoluble nitrogen, pH, and ammonia nitrogen. Increasing proportions of forage peanut increased the protein content and decreased the fiber content in the silage, while also reducing the production of ethanol and effluent. We recommend the inclusion of 40%–75% forage peanut in the sugarcane ensilage to improve the chemical composition and fermentation profile. Furthermore, inoculation with L. buchneri associated with forage peanut increases the concentration of antifungal acids in the silage and decreases the yeast population and ethanol production.

Allelopathy and allelochemical quantitative analysis in Pinto peanut (Arachis pintoi)

Pinto peanut (Arachis pintoi) considered as a perennial legume animal fed plant with good soil fertility improvement was uesed for its allelopathy that had been reported on the germination of Ageratum conyzoides L, Comnyza canadensis L. Cronq., Bidens pilosa L., Solanum lycopersicum and Capsicum annum. through the solutions extracted from different parts of pinto peanut on mustard greens (Brassica juncea), barnyardgrass (Echinochloa crus-galli) and junglerice (Echinochloa colonum). Consideration of the growth of hypocotyls and rootlets at 48 hours after incubation with pinto peanut extracts, results showed that 1.0 g/ml of the methanolic pinto peanut stem extract greatly inhibited 100% mustard greens growth, 77.7% and 93.5% the hypocotyls and rootlets growth of barnyardgrass, 57.2% and 92.7% the hypocotyls and rootlets growth of junglerice, respectively. The allelopathic activity after liquid-liquid extraction of the ethyl acetate phase greater than the aqueous phase. Allelopathic extract loading from C18 chromatographic column was purified by HPLC to obtain 6 phenolic compounds with the contents in 1 g fresh pinto peanut weight were 0.214 μg (cinamic acid), 0.8344 μg (caffeic acid), 7.7676 μg (coumaric acid), 2.2354 μg (ferullic acid), 0.045 μg (2-4 dimehydroxy benzoic) and 32.1162 μg (salicylic acid). These results should be accordingly considered in the production of biological herbicides.

Forage mass and nutritional value of elephant grass intercropped with forage legumes1

Forage-legume systems are a sustainable and competitive alternative for improving pasture yield and quality because of the symbiotic nitrogen fixation capacity and high nutritional value of legumes. This study aimed to evaluate the forage mass, nutritional value, and nutrient export rate in three forage systems (FS): FS1, with elephant grass (Pennisetum purpureum) (EG), annual ryegrass (Lolium multiflorum) (AR), and spontaneous growth species (SGS); FS2, with EG + AR + SGS + arrowleaf clover (Trifolum vesiculosum); and FS3, with EG + AR + SGS + forage peanut (Arachis pintoi ). The experiment was arranged in a completely randomized design, with three replicates, and repeated measures over time. Results of pre-grazing forage mass were 3.5, 3.8, and 3.9 t/ha, and crude protein export were 1.4, 2.1, and 2.3 t/ha, for the treatments FS1, FS2 and FS3, respectively. Highest crude protein, in situ dry matter digestibility and total digestible nutrients, and lowest neutral detergent fiber were found in the intercropping system with forage peanut, especially in winter. Nutritional values were also better in legume-systems than the non-legume system.

Competitive and spreading abilities of forage peanut in tropical mixed pastures

AbstractForage peanut (Arachis pintoi) is considered a legume ideotype for use in mixed pastures in humid tropical regions, but its adoption has been hindered by low availability and high prices of commercial seeds. However, there is a concern if breeding of high seed‐yielding cultivars could result in loss of compatibility with grasses. This study compared the competitive ability and spreading ability of 12 forage peanut genotypes with contrasting seed‐yielding potential in mixtures with Brachiaria humidicola in northern Brazil. These genotypes were previously selected for high performance under clipping in pure stands. Twenty‐five rooted stolons of forage peanut were transplanted to the central area (1 × 1 m) of each plot (5 × 5 m) seeded 35 days before with B. humidicola. The experiment used a randomized complete block design with five replicates per genotype and was evaluated under grazing from 6 to 30 months after pasture establishment using the intermittent stocking method. All genotypes persisted and increased their proportion in botanical composition over time. Spread of forage peanut stolons into surrounding B. humidicola sward varied from 0.56 to 1.46 m/year. Cultivar BRS Mandobi had the greatest competitive ability and cultivar Belomonte the greatest spreading ability. Two genotypes (cv. BRS Mandobi and accession BRA‐00064752‐9) were selected combining high seed‐yielding and high compatibility with B. humidicola. This is evidence that both traits (compatibility with grasses and seed yield) can be simultaneously improved in this legume. The results are discussed in terms of the ecology of grass‐legume mixtures and breeding of forage peanut.

Palisadegrass pastures with or without nitrogen or mixed with forage peanut grazed to a similar target canopy height. 2. Effects on animal performance, forage intake and digestion, and nitrogen metabolism

AbstractThe lack of nitrogen (N) input on pastures is the main limiting factor to increase animal performance in tropical regions. This 2.5‐year study assessed animal performance, forage intake and digestion, and N metabolism responses of three pasture treatments: (1) mixed Marandu palisadegrass—Brachiaria brizantha (Hochst. ex A. Rich.) R.D. Webster (syn. Urochloa brizantha Stapf cv. Marandu)—and forage peanut (Arachis pintoi Krapov. &amp; W.C. Greg. cv. BRS Mandobi) pastures (GRASS + LEGUME), (2) monoculture Marandu palisadegrass pastures with 150 kg of N/ha (GRASS + N), and (3) monoculture Marandu palisadegrass without N fertilizer (GRASS). Continuous stocking with variable stocking rate was used with a target canopy height of 20 to 25 cm. The average daily gain was greatest at GRASS + N and GRASS + LEGUME (p = .081). GRASS + N pasture had greatest stocking rate and liveweight gain per area (p &lt; .001 and p &lt; .001, respectively), followed by GRASS + LEGUME pasture. No differences between treatments were found for the dry matter forage intake (p = .729); however, GRASS + N and GRASS + LEGUME pastures had greater crude protein and digestible organic matter intakes than GRASS pasture (p = .007 and p = .083, respectively). Greatest microbial protein synthesis and efficiency of microbial synthesis were found for GRASS + N and GRASS + LEGUME pastures (p = .016 and p = .067, respectively). Apparent efficiency of N utilization and microbial protein/CP intake ratio was greatest at GRASS + LEGUME pastures (p = .009 and p = .042, respectively). Nitrogen application or the integration of forage peanut in grass pasture increases animal performance, forage digestibility, and microbial protein synthesis.

Protein and Carbohydrate Fractions in Warm-Season Pastures: Effects of Nitrogen Management Strategies

Nitrogen (N) management affects herbage production and chemical composition; however, information on the impact of tropical herbage on N and carbohydrate fractions is scarce. A two-year study was conducted to investigate the potential use of pintoi peanut (Arachis pintoi) compared with N fertilization of palisade grass (Brachiariabrizantha cv. Marandu) by evaluating the herbage chemical composition (fractionation of protein and carbohydrate), herbage mass and accumulation rate, herbage disappearance rate, and stocking rate of pastures. The experiment was conducted in a completely randomized design with three treatments, and four replications (paddocks) were used with twenty-one non-lactating crossbred dairy heifers. Treatments consisted of pastures of palisade grass without a N source (control), fertilized with urea (150 kg/ha/year; fertilized), or mixed with pintoi peanut (mixed). Inclusion of the legume increased concentrations of fractions A (p = 0.009), which is the soluble N compound, and B3 (p &lt; 0.001), which is slowly degraded true protein, compared with pastures fertilized with N and non-fertilized pastures. Nitrogen fertilization increased fraction B1 + B2 (p = 0.046), mainly true proteins, and decreased fraction C (p = 0.0007), indigestible protein, and neutral detergent fiber concentrations (p = 0.0003), contributing to increasing the nutritive value of the herbage. Additionally, N fertilization increased herbage mass (p = 0.004) and herbage allowance (p = 0.0001). Both N fertilization and biologically fixed N increased herbage allowance (p = 0.02) and accumulation rate (p = 0.02), as well as the crude protein content of herbage (p &lt; 0.0001) compared with non-fertilized pastures. Nitrogen fertilization increased true protein and decreased indigestible protein of herbage and promoted a greater herbage mass production, while the inclusion of legumes increased soluble protein and decreased the slowly degraded true protein of herbage. Both N management strategies increased herbage allowance and accumulation rate.

Palisadegrass pastures with or without nitrogen or mixed with forage peanut grazed to a similar target canopy height. 1. Effects on herbage mass, canopy structure and forage nutritive value

AbstractNitrogen (N) inputs to pasture systems coupled with grazing management strategies based on monitoring and control of canopy structure may provide conditions for greater productivity and enhanced forage nutritive value. This 2‐year study assessed canopy structure and nutritive value responses of three pasture treatments, namely, (1) mixed Marandu palisadegrass (Brachiaria brizantha [Hochst. ex A. Rich.] R.D. Webster [syn. Urochloa brizantha Stapf]) cv. Marandu and forage peanut (Arachis pintoi Krapov. &amp; W.C. Greg.) cv. BRS Mandobi pastures without N fertilizer (GRASS + LEGUME); (2) monoculture Marandu palisadegrass pastures fertilized with 150 kg N/ha (GRASS + N); and (3) monoculture Marandu palisadegrass without N fertilizer (GRASS). Grazing management was similar across pasture treatments, using continuous stocking and a target canopy height of 20–25 cm. Herbage mass was greater in GRASS + N and GRASS + LEGUME pastures than in GRASS in summer and spring (p = .014). The leaf:stem ratio in the grass mass (p = .731) was similar between treatments. Grass crude protein (CP) and in vitro digestible dry matter (IVDDM) were greatest in the GRASS + N pasture (p &lt; .001). Grass neutral detergent fibre (NDF) concentration was greater at GRASS and GRASS + LEGUME pastures than in GRASS + N (p &lt; .001). Forage peanut had a greater IVDDM and CP concentration and a lower NDF concentration than Marandu palisadegrass. Nitrogen application or the presence of the legume increased green herbage mass and improved forage nutritive value in canopies with similar height.

Physical quality of some types of grass on mixed planting with Arachis pintoi and organic fertilizing

Increased livestock productivity is largely determined by the availability of sufficient forage. Good forage is determined by digestibility, which is related to physical quality. This study aims to determine the physical quality of several types of grass planted with Arachis legumes and the provision of organic fertilizer. This study used a Randomized Block Design with a factorial pattern consisting of 3 types of grass planted with Arachis legumes (factor A) and fertilizing 2 types of solid and liquid organic fertilizer (factor B) with 3 replications. The treatment combinations are: R1C (Paspalum notatum with Arachis pintoi+Compost), R1B (Paspalum notatum with Arachis pintoi+Biourine), R2C (Paspalum conyugatum with Arachis pintoi + Compost), R2B (Paspalum conyugatum with Arachis pintoi +Biourine), R3C (Axonopus compresus with Arachis pintoi+Compost), R3B (Axonopus compresus with Arachis pintoi+Biourine). The results showed no significant difference (P>0.05) both in the mixture of some grass plants with Arachis pintoi and the provision of organic fertilizer on the physical quality of forage. In planting a mixture of Axonopus comprsus grass with Arachis pintoi showed average dry matter (DM), water regain capacity (WRC), and water solubility (WS). Whereas compost gets higher average values than biourine for dry matter, WRC and WS. The combination of mixed planting and fertilizing, compost showed the highest average, especially water solubility (WS). From this research it can be concluded planting a mixture of grass and legumes fed with compost on average is better for the physical quality of the grass, but not significantly different (P>0.05) from all treatments.

Olfactory Response of Plutella xylostella (Lepidoptera: Yponomeutidae) Adults to Refugia Plant

Selection of refugia plants is an important step when engineering the agroecological system. The refugia plants can be repellent or attractant to insect pests and in many species the role of each plant can be studied using the olfactory responses of the insect to volatile chemical cues emitted by the plant. The objective of this study was to determine the olfactory response of Plutella xylostella (Lepidoptera: Yponomeutidae) adults to several refugia plant candidates. Y-tube olfactometer tests were used to determine responses of P. xylostella to candidate plant species including: Ageratum conyzoides, Galinsoga parviflora, Synedrella nodiflora, Sphagneticola trilobata, Brassica rapa, Rorippa indica, Arachis pintoi, Ocimum basilicum, Apium graveolens, and Portulaca oleracea. Olfactory choice tests were conducted to compare preferences of insect. The results showed that R. indica, G. parviflora, and S. trilobata flowers attracted P. xylostella. R. indica and B. rapa leaves had high attractiveness for P. xylostella adults. At the same time, the A. graveolens, A. conyzoides, and O. basilicum leaves showed potential repellency. The conclusions of this study are R. indica and B. rapa have potential for use as trap crops, while A. graveolens, O. basilicum, and A. conyzoides have potential as repellent plants. Further study is necessary to test the olfactory response of P. xylostella’s natural enemies to these refugia plants.