Monitoring of Ganoderma spp. on the trees at Arboretum of Universitas Gadjah Mada, Yogyakarta, Indonesia: Implications for health care recommendation of old trees

The arboretum of Universitas Gadjah Mada (UGM), Yogyakarta, established in 1963, is host to various plants and trees originating from across Indonesia. Due to poor management and climate change, several cases of tree death and decline related to the Ganoderma sp. attack have been reported since 2015. The aims of this research were to evaluate the occurrence of root rot disease and to monitor the spatial and temporal distribution of Ganoderma spp. Completely survey on 638 trees with DBH more than 10 cm, monitored the number of basidiocarps attached on each infected species tree, and assessed the leaf and canopy condition were conducted on 2018 to 2021. The result showed that 0.78 % of trees with more than 10 cm diameter were infected by Ganoderma sp. since 2018 and become 1.57% in 2021. The species trees of Pterygota alata (1 tree), Pterocarpus indicus (1 tree), and Adenanthera pavonina (8 trees) were attacked by Ganoderma with a disease severity index of 25% to 100% in September 2021. The spatial pattern of trees associated with Ganoderma was random. However, since the density of trees at the arboretum is dense, the potential Ganoderma spreading through root contact will be high. Regular monitoring for early detection has to be conducted to prevent advanced infection and to set health care recommendations for infected trees with a high scientific value.

Pests, pathogens, pathogenic diseases, and diseases control strategies of sal (Shorea robusta) in Nepal

Sal (Shorea robusta) is one of the most indispensable species in Nepal, both ecologically and economically. This paper aims to provide updated guidance for the management and protection of this species in the future from various pests and pathogens. We reviewed 38 articles from Google Scholar and Research gate with keywords "Shorea robusta”, “Hoplocerambyx spinicornis”, “Polyporus shoreae”, “Heart rot”. S. robusta has the most insect fauna among the forest tree species. Out of the 346 insects reported on S. robusta, around 155 species of insects are associated with living trees. Hoplocerambyx spinicornis is the most destructive insect pest, wreaking havoc on S. robusta. Polyporous shoreae is the main cause of root rot in S. robusta, and spreads through root contact or root grafting. Heart rot in S. robusta is caused by the fungi Hymenochaete rubiginosa, Fomes caryophylli, and F. fastuosus. During the harvesting of S. robusta, the majority of the tree was observed to be faulty, resulting in a large amount of waste wood. The best way to determine the pathogen's "Achilles' heel" is to consider its life cycle. The Nepalese famous saying "prevention is better than cure" may be applicable in the management of S. robusta insect pests and pathogens. The current paper critically addresses these issues and argues the need for an improvised package of activities for insect pests, pathogens, prevention, and their control.

Evidence of considerable C and N transfer from peas to cereals via direct root contact but not via mycorrhiza

Intercropping of legumes and cereals is an important management method for improving yield stability, especially in organic farming systems. However, knowledge is restricted on the relevance of different nutrient transfer pathways. The objective of the study was to quantify nitrogen (N) and carbon (C) transfer from peas to triticale by (1) direct root contact (= R), (2) arbuscular mycorrhizal fungi (AMF; = A), and (3) diffusion (= D). Pea (Pisum sativum cv. Frisson and P2) and triticale (Triticum × Secale cv. Benetto) plants as intercrop were grown for 105 days. Treatment ADR enabled all transfer paths between the two crops. Treatment AD with root exclusion enabled AMF and diffusion transfer between peas and triticale. Treatment A with a diffusion gap barrier only allowed AMF transfer. Pea plants were labelled every 14 days with a 13C glucose and 15N urea solution, using the cotton wick technique. Direct root contact resulted in the highest pea rhizodeposition and thus the largest absolute amounts of N and C transfer to triticale. Root exclusion generally changed composition of rhizodeposits from fine root residues towards root exudates. Pea plant-N consisted of 17% N derived from rhizodeposition (NdfR) in treatment ADR but only 8% in the treatments AD and A, independently of pea variety, whereas pea plant-C consisted of 13% C derived from rhizodeposition (CdfR), without pea variety and transfer path treatment effects. Averaging all transfer path treatments, 6.7% of NdfR and 2.7% of CdfR was transferred from Frisson and P2 to triticale plants. Approximately 90% of this NdfR was transferred by direct root contact from Frisson to triticale and only 10% by AMF, whereas only 55% of CdfR was transferred to triticale by direct root contact, 40% by AMF and 5% by diffusion. Similar percentages were transferred from mutant P2 to triticale. Root exclusion generally changed RD composition from fine root residues towards root exudates.

Evaluation of Demographic, Radiological and Intraoperative Factors For Assessment of Postoperative Pain And Complications In Surgical Removal Of Impacted Mandibular Third Molar – A Prospective Study

Third molars usually erupt within the age of 17 – 21years. Usually, due to the evolution of human jaws, the size is decreasing leading to the impacted tooth. An impacted tooth may lead to external resorption of the adjacent tooth, trismus, infection, etc. Many studies have been reported in the literature for evaluating the surgical difficulty and postoperative complications secondary to impacted third molars. This study includes a sample of 100 subjects evaluated for the surgical difficulty and postoperative complications. Various demographic, radiological, and intraoperative factors were evaluated which may lead to postoperative complications. Factors responsible for postoperative sequelae were also evaluated with complications. Postoperative pain after 4 hours and 7 days was assessed to mark the factors commonly responsible. Pain at 7th postoperative day was significant involving factors like fully impacted, horizontal impaction, level C, no/very little retromolar space, and root contact. Postoperative com­plications were not reported in this study.

Spatiotemporal Spread of Abnormal Vertical Growth of Macadamia in Australia Informs Epidemiology

Australian macadamia production is threatened by a disorder known as abnormal vertical growth (AVG), for which the etiology is unknown. AVG is characterized by vigorous upright growth and reduced lateral branching, flowering, and nut set that results in over 70% yield loss annually. Six commercial macadamia orchards were surveyed in 2012 and again in 2018 to examine spatiotemporal dynamics of the epidemic. Data were subjected to point-pattern and geostatistical analyses. AVG incidence in all orchards showed a better fit to the beta-binomial distribution than the binomial distribution. AVG incidence in the different orchards varied between 5 and 47% in 2012, and 13 and 55% in 2018 and the rate of spread was slow, averaging at about 2% increase in disease incidence per annum. Spatial patterns of AVG were highly aggregated on both survey years and spread was mainly between neighboring trees in a row or trees that were opposite to each other in different rows. Semivariograms showed large range values (approximately 15 to 120), indicating aggregation of AVG-affected trees beyond quadrat levels. Furthermore, clusters of disease were mainly at the edge of the orchard on the first survey date and the disease progressed toward the center of the orchard over time. It is concluded that AVG is caused by an infectious agent, and based on patterns of spread, we hypothesize that spread is facilitated by root grafting or root-to-root contact. Furthermore, a vascular-limited pathogen could be involved that modulates plant hormone production.

Root Contact between Maize and Alfalfa Facilitates Nitrogen Transfer and Uptake Using Techniques of Foliar 15N-Labeling

Belowground nitrogen (N) transfer from legumes to non-legumes provides an important N source for crop yield and N utilization. However, whether root contact facilitates N transfer and the extent to which N transfer contributes to crop productivity and N utilization have not been clarified. In our study, two-year rain shelter experiments were conducted to quantify the effect of root contact on N transfer in a maize/alfalfa intercropping system. N transfer occurred mainly one direction from alfalfa to maize during the growth period. Following the N0 treatment, the amount of N transfer from alfalfa to maize was 204.56 mg pot−1 with no root barrier and 165.13 mg pot−1 with a nylon net barrier, accounting for 4.72% and 4.48% of the total N accumulated in maize, respectively. Following the N1 treatment, the amount of N transfer from alfalfa to maize was 197.70 mg pot−1 with no root barrier and 139.04 mg pot−1 with a nylon net barrier, accounting for 3.64% and 2.36% of the total N accumulated in the maize, respectively. Furthermore, the amount of N transfer without no root barrier was 1.24–1.42 times higher than that with a nylon net barrier regardless of the level of N addition. Our results highlight the importance and the relevance of root contact for the enhancement of N transfer in a maize/alfalfa intercropping system.

A Novel Method to Search for the Wheel–Rail Contact Point

This paper proposed the normal contact searching method (NCSM), a novel method to search for the wheel–rail contact point, which utilizes the normal maximum penetration distance between wheel and rail as the judgment condition. The contact point found by the NCSM can better represent the center of the wheel–rail contact patch which is considered more reasonable than the commonly used vertical contact searching method (VCSM), the latter adopts the vertical minimum distance to determine the wheel–rail contact point. The differences between these two methods are analyzed and compared for the same contact point situation and with same motion parameters. The results show that, for the Chinese LMA wheelset and CHN60 rail profiles, these two methods have slight differences for the same contact point situation. For a wheelset with a lateral displacement less than 7.0[Formula: see text]mm and with no yawing, the NCSM’s contact point is very close to VCSM’s, so both methods are suitable for the dynamic calculation. For a wheelset with a lateral displacement greater than 7.0[Formula: see text]mm or with yawing, an unreasonable jump occurs at the wheel–rail contact point and wheelset angle root contact by applying VCSM, while the NCSM has only small discrete jump on the wheelset tread contact. In this case, the NCSM instead of VCSM should be used in the dynamic analysis.