Resistance of bmr energy sorghum hybrids to sugarcane borer and fall armyworm

The lower lignin content in plants species with energy potential results in easier cellulose breakdown, making glucose available for ethanol generation. However, higher lignin levels can increase resistance to insect attack. The objective of this work was to evaluate the susceptibility of a bmr-6 biomass sorghum (a mutant genotype with a lower concentration of lignin) to important pests of energy sorghum, Diatraea saccharalis and Spodoptera frugiperda. Experiments were performed in the laboratory and greenhouse to evaluate the development of these pests on the biomass sorghum bmr hybrids BR007, BR008, and TX635 and their respective conventional near-isogenic genotypes (without the bmr gene). The lignin content was higher in non-bmr hybrids, but the evaluated insect variables varied between treatments, not being consistent in just one hybrid or because it is bmr or not. The lowest survival of S. frugiperda was observed in the BR008 hybrid, both bmr and non-bmr. The S. frugiperda injury scores on plants in the greenhouse were high (>7) in all treatments. For D. saccharalis, there was no difference in larval survival in the laboratory, but in the greenhouse, the BR007 hybrid, both bmr and non-bmr, provided greater survival. Due the need to diversify the energy matrix and the fact that greater susceptibility of the bmr hybrids to either pests was not found in this study, these results hold promise for cultivation of these biomass sorghum hybrids for the production of biofuels.

Keragaan Tanaman Kacang Tanah Pasca Serangan Hama Kutu Kebul Bemisia Tabaci Genn

Peanut is one of the plants that are widely cultivated by farmers. Biotic and abiotic stresses are one of the barriers to peanut productivity. The biotic attack of the whitefly Bemisia tabaci infestation on peanuts impacts the performance of the plant itself. The purpose of this study was to determine the performance of peanut plants after being attacked by whiteflies.The research was carried out in 2019 using 10 peanut genotypes arranged according to a completely randomized design and repeated three times. The research plants were infested with whitefly and then observed several characters, including the number of flowers, number of gynophores, number of branches, number of roots, root length, plant height, number and weight of pods, number and weight of seeds, and crop yield index. The results showed that the groundnut infested with whitefly contained sooty dew as a direct insect attack. The population and sooty dew caused the number of flowers and branches to be low, the value of the number of dry pods and dry pod weight was low, the dry seed weight was low, and the crop harvest index was also low.

Health identification of Shorea javanica Koord. and valeton in nursery

Shorea javanica Koord. and Valeton is an identity tree of Lampung Province. The dammar of this species, locally known as damar mata kucing (cat-eye resin). The population of S. javanica is mostly in Repong Damar and grows naturally in Bukit Barisan Selatan National Park. Within a decade, the damar mata kucing production was decreased. The threat of deforestation, land degradation, and the scarcity of regeneration were some of the causes. One of the important efforts that could be done was to procure quality seedlings in the nursery. Knowledge of the health condition of seedlings in a nursery is very important in supporting plant cultivation success. Plant insects and diseases were one of the determining factors. This study aims to determine the health of S. javanica seedlings in South Lampung Permanent Nursery, which Way Seputih Way Sekampung Watershed Management Center and Protected Forest manage. This seed health identification activity used the Systematic Random Sampling method with a sampling intensity of 10%. The samples obtained were carried out by identifying the type of damage, location of damage, and severity of all S. javanica seeds sampled using criteria and standards for crop assessment results according to the International Center’s Environmental Monitoring standards Assessment Program (EMAP). Based on the result of the research, from 100 seedlings of S. javanica that was observed 75% of seedlings are unhealth, and 25% of seedlings are healthy. Among the 75% unhealthy seedling, 2% were dead. The intensity of total attack is about 73%, the intensity of insect attack is about 41%, and disease attack intensity is 32%, with the highest attack severity 30-39%. The results showed that the live percentage of S. javanica seedlings was 98% which was in the very good category.

Low Tunnels inside Mediterranean Greenhouses: Effects on Air/Soil Temperature and Humidity

The main objective of this work was to analyze the microclimate generated inside a low tunnel (floating row cover) installed in an Almería-type greenhouse. Low tunnels are commonly used in the open field to protect plants against insect attack and to improve the production of muskmelon and strawberry. Floating row covers can also be used inside greenhouses during the first few weeks after the transplantation of muskmelon and watermelon crops in spring-summer cycles. This work was carried out during the first weeks of a watermelon culture (Citrullus lanatus Thunb.) growing with a polyethylene row cover inside an Almería-type greenhouse (2115 m2). Air temperature and humidity, plant temperature and soil temperature and humidity were measured in the greenhouse inside and outside the row covers. During the three days of measurement, all greenhouse vent openings were closed. The use of the low tunnels increased average air temperature around plants from 24.0 ± 9.0 °C to 26.9 ± 9.7 °C. A maximum difference in air temperature of about 5.9 °C was observed at noon. The average daily temperature of the crop was 28.2 ± 11.8 °C inside the row cover and 24.6 ± 8.9 °C without it. Similarly, the absolute humidity of air was clearly higher inside the low tunnel (0.0201 ± 0.0098 g/g) than around the plant rows without floating cover (0.0131 ± 0.0048 g/g). The soil temperature was also higher inside the low tunnel compared to the area without this second plastic cover. The effect of the tunnel decreased with depth, with average temperature differences of 1.2 ± 0.5 °C on the soil surface and 0.6 ± 0.5 °C at 20 cm depth.

OCCURRENCE OF INSECT PESTS IN FRUITS OF Caryocar brasiliense (CARYOCARACEAE) IN THE NORTH OF MINAS GERAIS

ABSTRACT Caryocar brasiliense Camb. is a typical species from the Cerrado that represents a relevant income for the population where the fruit is produced. The ocorrence of insect pests provokes damage in the fruit and making its commercialization unfeasible. Then, this study aimed to identify the pest insect the fruit and the pit; to compare the morphological features of the fruit and pit and the damage caused by insects among mother plants and their origins and correlate the fruit and pit morphological features with the damage caused by the insects. Three different origins were evaluated, 12 mother plants by origin and ten fruit by mother plant. All the fruit were opened, checked for the insect damage and the fruit and pit morphological variables were determined. The insects that caused damage to the pequi embryo were identified as Carmenta sp. (Lepidoptera: Sesiidae) and Amblycerus sp (Coleoptera: Chrysomelidae). The probability analysis showed significant effect on the mother plants and origins for the percentage of fruit and pit attacked where the location of Laje Velha obtained the lowest rates of the insect attack. The fruit and pit of the Fruta de Leite were bigger and heavier than the others, while the correlations among the predation rate and the other morphological variables of the fruit and pit were not significant. Amblycerus sp. and Carmenta sp. may be considered potential pests of pequi, with the risk of compromising the pequizeiro populations and the regional economics.

Ferulago campestris Essential Oil as Active Ingredient in Chitosan Seed-Coating: Chemical Analyses, Allelopathic Effects, and Protective Activity against the Common Bean Pest Acanthoscelides obtectus

Ferulago campestris is an aromatic plant, distributed in Mediterranean Europe, and a source of essential oils (EOs) regarded as promising alternatives to synthetic herbicides and pesticides. F. campestris EO, hydrodistilled and analyzed, was tested for its antigerminative activity and for its effect on radicle elongation, hydrogen peroxide concentration, and lipid peroxidation on four infesting weed species (Papaver rhoeas, Taraxacum campylodes, Poa annua, and Setaria verticillata) and on Phaseolus vulgaris. Its repellent ability was also tested against Acanthoscelides obtectus, a pest commonly affecting P. vulgaris during storage. Moreover, a chitosan coating layer was developed with the addition of F. campestris EO and tested for its toxic and oviposition-deterring effects against A. obtectus. Myrcene, α-pinene, and γ-terpinene were detected as the main compounds in F. campestris EO. The EO demonstrated a selective in vitro antigerminative activity towards the weed species, without affecting the bean seeds. Moreover, the chitosan coating layer exerted a dose-dependent repellent effect against A. obtectus adults, thus effectively protecting the bean seeds, while preserving their germinative ability. To the best of our knowledge, this is the first report on a chitosan–EO coating proposed with the aim of protecting bean seeds for sowing from insect attack.

​Insect Plant Interaction with Reference to Secondary Metabolites: A Review

Plant and herbivorous insect share a contradictory but everlasting relationship. To cope with the herbivores, plant invested its energy in the production of various defensive chemicals which are known as plant secondary metabolites (PSMs). During coevolution with plants, insects also adapted themselves to counter plant defensive mechanisms. The secreted saliva and ovipositional fluids of insects induce the production of secondary metabolites in plants. Plants also produce compounds constitutively in the tissues that are susceptible to insect attack. These compounds reduce insect growth and development of insects through interfering with the developmental phases, acting as feeding deterrent, reducing nutritive value, affecting protein digestion and the production of substances toxic to them. On the contrary, insect’s adaptations to PSMs include the detoxification of plant toxins, conversion of the toxic compounds into conducible form for its growth and development, development of feeding choice based on the concentration of PSMs, quicker absorption and elimination as feces and obtaining the help of symbiotic intestinal microorganism to inactivate toxic materials. Furthermore, insects also utilize PSMs as chemical cues mediated through their chemoreceptive systems. The selection of host plants by monophagous insect is sometimes concentrated on the production of particular PSMs. Secondary metabolites also act as attractant to insect pollinators by exhibiting distinctive odors. Insects also store toxic PSMs which are used by them against their predators and in giving protection to eggs. However, this intrinsic capability of plants to produce defensive chemicals in response to insect attack should be explored to a wide extent to optimize the performance of PSMs.

A Mechanistic insight into chemical cues and interactions involved in herbivory induced jasmonate mediated plant defense mechanism

The first step in plant defense mechanism is to sense the insect attack stimulus. Plant sensitivity of an insect attack is the first step of defense. Molecules generated by the oral secretion of the insect interact with the plant receptors to trigger plant defense mechanisms. We selected some highly cited insect elicitors molecules, volicitin, caeliferin, bruchin which interact with plant defense by interacting with plant elicitors (systemin, inceptin and peps) located on the plant cell surface. This interaction activates plant receptors SYR1, LRR, PEPR and triggers downstream defense signaling. The octadecanoid pathways, involving enzymes allene oxide synthase (AOS) and Hydroxyperoxide lyase (HPL) are activated. These enzymes mediate production of green leafy volatiles and Jasmonic acid by interacting with hydroxperoxide molecules. We docked the elicitors with receptors and enzymes with substrates in the pathway of JA production. Phe was found to be an important amino acid that interacts with 13- hydroxyperoxides in the case of AOS to produce JA but not in the case of HPL. JA is converted to JA-Ile which shows strong binding with COI1 and COI1-JA-Ile complex docked with JAZ which showed strong interaction with five hydrogens and one salt bridge bond. AOS and HPL showed less than 40% identity for sequence and structure alignment. AOS and HPL had shown an interaction between each other and showed a common interaction partner of the Lipoxygenase family. HPL shows interaction with ADH2 (Alcohol dehydrogenase) involved in GLVs production. AOS also showed interaction partner AOC, COI1 and OPR1 which are involved in JA-induced plant defense mechanism.

Advances in understanding plant root responses to root-feeding insects

This chapter presents an overview of the interactions between plant roots and root-feeding insect herbivores, focussing on changes in growth and physiology and crucially how roots are defended against insect attack. Several reviews have covered the ecology and management of insect root herbivores, together with their interactions with the abiotic and biotic soil environment. Therefore, the chapter focuses particularly on advances in our understanding of how plant mutualistic fungi may affect root-herbivores. This is an emerging area of research, with many attendant knowledge gaps, but we argue that this is an important component of how plants resist attack by belowground insect herbivores.

Terminalia arjuna Leaf Gall: The Possible Treatment for Sickle Cell Anaemia

Objective: To check the presence of various secondary metabolites produced in the plant under study Terminalia arjuna (Roxb.) Wight and Arn. post insect attack and gall formation. Study Design: Terminalia arjuna (Roxb.) Wight and Arn, a well known plant involved in treating heart ailments in the Ayurvedic system of medicine for centuries. The plant’s astringent bark exhibits cardioprotective properties and is commonly used in the treatment of hypertension, angina and coronary artery disease. T. arjuna plant suffers from gall development in its leaves due to the attack of an hemipteran insect Trioza fletcheri minor. Insect attack acts as a stress stimulus for the plant to produce various bio-active compounds as a part of their defence mechanism. The present study was intended for the identification of various compounds present in the crude extract obtained from the healthy and galled leaves of Terminalia arjuna. Place and Duration of Study: Experiments performed in the Plant pathology and tissue culture laboratory, Department of Botany University of Rajasthan, Jaipur, between April 2018 to March 2019. Methodology: Various methods are employed for the identification of possible bio-active compounds present in the plant crude extract, GC-MS (Gas Chromatography- Mass Spectroscopy) is one such method. To check the presence of phytochemicals produced post insect attack and infection in T. arjuna normal and galled leaves, Gas Chromatography-Mass Spectroscopy (GC-MS) of the methanolic extract was conducted. The normal healthy leaves and the galled leaves were collected, shade dried, pulverized and then soxhlet extracted for GC-MS analysis. Results: GC-MS analysis of methanolic extract of Terminalia arjuna leaves and galls confess the presence of 57 compounds in the gall extract while 21 compounds in normal (uninfected) leaf extract. The gall extract revealed the presence of various novel and medicinally important bio-active compounds, one of them was 5-Hydroxy Methyl Furfural (5-HMF). Conclusion: 5-HMF, an aromatic aldehyde is an economically important chemical compound and well-known for its wide application in various fields. It is an efficient anti-sickling agent and has undergone pre-clinical testing as a potential treatment for the fatal sickle cell disease. Qualitative phytochemical screening revealed the presence of various bio-active compounds both in leaf and gall methanolic extract of Terminalia arjuna, thus proving the plant’s pharmaceutical importance. This study result will make a way for further research in plant’s pharmacological research.