Herbicide-Resistant Invasive Plant Species Ludwigia decurrens Walter

Ludwigia decurrens Walter is a dicotyledonous plant belonging to the family Onagraceae. It is native to Central Eastern USA but has been spreading quickly and has naturalized in aquatic and riparian ecosystems (including rice paddy fields) in many countries; therefore, it is now considered an invasive noxious weed. L. decurrens is highly competitive with rice and causes a significant reduction in rice production. The objective of the present study was to evaluate the efficacy of the herbicide penoxsulam for the control of L. decurrens in rice fields. The seeds of L. decurrens were collected from four villages in Indonesia, and penoxsulam was applied to L. decurrens in seven dosages (0, 2.5, 5, 10, 20, 40, and 80 g a.i. ha−1) 3 weeks after seed sowing. The plant populations from Hegarmanah, Jatisari, and Joho showed complete mortality at the recommended dosage of penoxsulam (10 g a.i. ha−1). However, the plants from Demakan grew, flowered, and produced seeds 56 days after treatment with 40 g a.i. ha−1 of penoxsulam. The resistance index value of the population was 36.06. This is the first report of a penoxsulam-resistant weed from a dicotyledonous plant species and also the first report of a herbicide-resistant population of L. decurrens. The appearance of herbicide-resistant L. decurrens is a serious issue from both an environmental and an economic perspective, especially since protected forest and freshwater ecosystems are located at a short distance from the study area. Further research is needed to evaluate herbicide mixtures and/or the rotation of herbicide action sites. The identification of the penoxsulam-resistance mechanism in L. decurrens is also necessary to develop a herbicide resistance management strategy.

Misturatosphaeria viridibrunnea sp. nov. (Teichosporaceae, Pleosporales) from Thailand

We introduce a new species, Misturatosphaeria viridibrunnea, isolated from dead branches of an unidentified terrestrial dicotyledonous plant in Chiang Rai, Thailand. The new species is characterized by fusiform, 1-septate, olivaceous brown to dark brown, regularly 4-guttulate ascospores with slightly longitudinal striations on surface. Misturatosphaeria viridibrunnea is easily distinguishable from other species in the genus by smaller-sized ascomata, asci and ascospores. Phylogenetic analyses using a combined gene analysis of LSU and ITS sequence data indicated that the new species belongs to Teichosporaceae (Pleosporales). A detailed morphological description and illustration of the new species is provided.

PERCENTAGE OF TOTAL PLANT MONOCOTS AND DICOTS IN SERDANG MENANG VILLAGE, SIRAH PULAU PADANG SUB-DISTRICT, OGAN KOMERING ILIR DISTRICT.

Dicotyledonous plant is a plant that has the characteristic that transporter tissue files are in a loop, while monocot plants are plants that have the characteristic that the tissue transporter beam spread. Morphological differences between plants dicots and monocots can be seen from the roots, stems, leaves and flowers. Dicotyledonous plants rooted riding, rod cambium, pinnate leaves and flower jewelry section consisting of 2, 4, 5 or multiples thereof. Monocot fibrous roots, stems not cambium, leaves curved, parallel, flower jewelry section consists of 3 or multiples thereof. The research was conducted on Sunday, May 15, 2016, in the Serdang Menang village, Sirah Pulau Padang, Ogan Komering Ilir. Tools and materials used are stationery and notepads. Number of dicotyledonous plants located in the village of Serdang Menang totaling 94 species, while the monocot plants totaling 30 species were found. Total comparison 75, 8% (plants dikotil) and 24, 2% (plants monocots).

Two novel species of Neoaquastroma (Parabambusicolaceae, Pleosporales) with their phoma-like asexual morphs

The monotypic genus Neoaquastroma (Parabambusicolaceae, Pleosporales) was introduced for a microfungus isolated from a collection of dried stems of a dicotyledonous plant in Thailand. In this paper, we introduce two novel species, N.bauhiniae and N.krabiense, in this genus. Their asexual morphs comprise conidiomata with aseptate and hyaline conidia. Neoaquastromabauhiniae has ascomata, asci and ascospores that are smaller than those of N.krabiense. Descriptions and illustrations of N.bauhiniae and N.krabiense are provided and the two species compared with the type species of the genus, N.guttulatum. Evidence for the introduction of the new taxa is also provided from phylogenetic analysis of a combined dataset of partial LSU, SSU, ITS and tef1 sequence data. The phylogenetic analysis revealed a distinct lineage for N.bauhiniae and N.krabiense within the family Parabambusicolaceae.

POPULASI DAN SERANGAN KUTU PUTIH PEPAYA, PARACOCCUS MARGINATUS (HEMIPTERA: PSEUDOCOCCIDAE) PADA TANAMAN PEPAYA DI DAERAH DATARAN RENDAH SUMATERA SELATAN

Populations and damage by the papaya mealybug Paracoccus marginatus (Hemiptera: Pseudococcidae) on papaya inlowland areas of South Sumatera. One of the main problems in papaya cultivation today is the presence of a newlyintroduced pest, the white papaya mealybug, Paracoccus marginatus (Hemiptera: Pseudococcidae). This study aimed toobserve the mealybug populations and its damage percentage in papaya plants and to identify its host plants in SouthSumatera. The study was carried out on the fruit and vegetable producing area in Indralaya, South Sumatera. The survey wasconducted on papaya plantation plots with a minimum size of 1000 m2. Data from the observation indicated that populationsof P. marginatus on papaya fruit were not significantly different to those on papaya leaves, except for the first observation inthe rainy season. In general, the percentages of mealybug damages were not affected by the season and the percentages ofdamage on the leaves were not different from those on the fruits of the papaya plants. Inventory of P. marginatus host plantson the area resulted in a total of 12 species of host plants dominated by dicotyledonous plant species. The host plants werefrom 11 families, i.e. Anacardiaceae, Caricaceae, Cucurbitaceae, Euphorbiaceae, Fabaceae, Myrtaceae, Rosaceae, Rutaceae,Sapindaceae, Sapotaceae, and Solanaceae.

Anatomical features of Bougainvillea (Nyctaginaceae)

Two potted plants of Bougainvillea were obtained from a local nursery to explore their anatomical features using a variety of microscopical methods and stains. Various anatomical structures revealed were consistent with previous literature and these features were related to the natural habitat and established internal and external defenses of the plant. Results confirmed that the Bougainvillea is, in fact, a dicotyledonous plant that has evolved defensive features that permit its survival in hot and dry environments. Results indicated that features such as woody spines, the crystal inclusions in cells and the anomalous growth pattern are relatively unique to this species and important for its survival against predators.

Efficiency of a herbivore–plant interaction: conversion of biomass from flax (Linaceae) to aphid, Macrosiphum euphorbiae (Hemiptera: Aphididae)

The specific impact of the aphid Macrosiphum euphorbiae (Thomas) on seedlings of common flax, Linum usitatissimum L., is 3.317 mg/mg, quantified as the dry mass of plant tissue required to produce a unit of herbivore tissue. This measure of the efficiency of biomass conversion between trophic levels for the aphid–flax interaction is similar to that previously reported for seven species of aphid on monocotyledonous cereals (Poaceae), but lower than that for two species of aphid on a species of Brassicaceae, a dicotyledonous plant. Therefore, the interaction between M. euphorbiae and the dicot, flax, does not support the hypothesis that aphids have less impact on monocots than on dicots.