Effects of intercropping on temperate grasses canopy architecture and nutritive profile

This paper aimed to evaluate the impact of intercropping between oats and triticale species, over three defoliation cycles. The experiment occurred in two winters in a row, and was in split-plot randomized complete blocks design (20 plots) with five species combination, four blocks and three defoliations. The main plots were the species combination: black oat (Avena strigosa cv. IAPAR 61) – BO, white oat (Avena sativa cv. IPR Emerald) – WO, triticale (X Triticosecale Wittmack cv. Tpolo 981) – T; and the intercropping: black oat + triticale – BOT, and white oat + triticale - WOT. The sub-plots were the three defoliations cycles initially scheduled to be every 28 days. The intercropping between oats and triticale did not affect the accumulated dry matter yield (DM), but it also improved the pastures, as an increase on crude protein content (CP) (about 1.85% greater in WOT than WO; and 2.7% greater in BOT than BO). The number of leaves was also increased by the intercropping, from 4.2 (WO) and 3.7 (BO) to 7.6 (WOT) and 7.2 (BOT) leaves per main stem. Over the defoliation cycles, the maximum average of growth rate (2.72 t DM ha-1 ºCd-1), tiller per plant (10 tillers plant-1) and main tiller height (53.2 cm) were unanimously observed at third defoliation. The changes observed did not reduced the nutritional quality of the pastures, therefore both are highly indicated to these conditions.

Comprehensive evaluation of the allelopathic potential of Elymus nutans

Drooping wildryegrass (Elymus nutans) has been widely planted together with other perennial grasses for rebuilding degraded alpine meadow atop the Tibetan Plateau. However, the rebuilt sown pastures begin to decline a few years after establishing. One of the possible causes for degradation of sown grassland may come from allelopathy of planted grasses. The purpose of this study was to examine allelopathic potential of drooping wildryegrass. Three types aqueous extracts from drooping wildryegrass and its root zone soil were prepared and 5 highland crops and 5 perennial grasses were used as recipient plants. Drooping wildryegrass exhibited strong allelopathic potential on germination and seedling growth of 5 crops germination and growth, but different crops or perennial grasses respond to the extracts differently. The pieces extract has stronger inhibition than others. Hulless barley, oat and Chinese fescue were the most affected, while quinoa and Siberian wildryegrass were the least affected. Drooping wildryegrass presented less influence on Kentucky bluegrass and crymophylla bluegrass than on Chinese fescue. It is recommended that the species combination of mixture for restoration should consider allopathic effects of the co-seeding and decrease the seeding rate ratio of drooping wildryegrass. The annual dicot crop quinoa and rape seeds can be used as alternative subsequent crop for seed field of drooping wildryegrass monoculture.

Diversity and Gradient Analysis of Common Yew (Taxus Baccata L.) Communities in Eastern Hyrcanian Forests, Northern Iran

Aims: To outline syntaxonomical synthesis of yew (Taxus baccata L.) in the eastern of Hyrcanian forest and to identify their main environmental gradients. Location: Jahan-Nama protected area (JNPA) as a unique yew population with heterogeneous floristically composition in the east of Hyrcanian forests, Northern Iran. Methods: Vegetation units were classified using modified TWINSPAN and were translated into syntaxonomic system. Syntaxa were determined by re-arrangement of each relevé based on diagnostic species occurrences and expert knowledge with the aim to increase the floristic distinctiveness of vegetation units. Syntaxa were finally evaluated by diagnostic species and environmental parameters according to phi- values and ANOVA, respectively. DCA was used to visualize the dissimilarity of syntaxa and their relationships with the environmental factors. We also used species combination concept for determining diagnostic species in the second association. Results: The classification of JNPA yew forests resulted in 6 Vegetation unites. These patterns were translated into four associations, two sub-associations and two variants. (Asso.1) Fago orientalis-Taxetum baccatae is found in northern aspects with lower slopes and higher soil depth; (Asso.2) Aceri velutini-Taxetum baccatae is occurring in the moderate but rocky slopes. Asso.1 and Asso.2 are the same in altitude and involving Carpinus betulus as a co-dominant. (Asso.3) Carpino betuli-Carpino orientale-Taxetum baccatae developed in the intermediate slopes. (Asso.4) Carpino orientale -Taxetum baccatae appeared in the highest slope of northeast and northwest aspects with shallow soil depth. The main factors determining the species composition of the JNPA syntaxa are slope, eastness, elevation and clay content. Conclusions: Our study provides the first syntaxonomic of yew communities in east of Hyrcanian forests and it also used the concept of species combination for exploring diagnostic species for proposing Carpino betuli- Carpino orientale- Taxetum baccatae association. We also showed that yew could be associated with different plant species which are distributing in different site suitability. It caused to have various yew syntaxa in JNPA and considerably reiterate high floristically and ecologically capacity of this area.

Determination of suitable species combination for good aquaculture practice based carp fattening in ponds under drought prone barind area of Bangladesh

Increased temperature, decreased water level and reduced culture period of the ponds with lack of guidelines in selecting appropriate stocking size, density and combination of species are major constraints for safe production of fattening based carps in drought prone barind area of Bangladesh. In order to address these problems, an experiment was conducted during July-December, 2018 to determine the suitable species combination for fattening ponds of overwintered carps in Tanore upazila (sub district) of Rajshahi district, Bangladesh. Three different combinations of surface (G. catla and H. molitrix), column (L. rohita) and bottom (C. cirrhosus and C. carpio var. specularis) feeding carp species were tested under 3 treatments (T1, T2 and T3), each with 3 replications: T1 (Surface-30%, column-40%, and bottom-30%), T2 (Surface-40%, column-30%, and bottom-30%) and T3 (Surface-35%, column-35%, and bottom-30%). Application of good aquaculture practices in the studied ponds was found to improve the environmental conditions of pond. Significantly (P< 0.05) highest fish yield was obtained from treatment T2 which was 21.47% and 11.89% higher than T1 and T3, respectively. Significantly (P<0.05) highest cost benefit ratio was recorded with treatment T2 (0.42±0.02) followed by T3 (0.31±0.01) and T1 (0.21±0.01), respectively. Inclusion of appropriate number of fishes at different water layers of pond favoured the yield and economics of carp fattening. The study also suggests focusing on optimal stocking density together with the formulation of low cost feed for carp fattening in ponds under barind area of Bangladesh.

Stressful times in a climate crisis: how will aphids respond to more frequent drought?

AimAphids are abundant in natural and managed vegetation, supporting a diverse community of organisms and causing damage to agricultural crops. Using a meta-analysis approach, we aimed to advance understanding of how increased drought incidence will affect this ecologically and economically important insect group, and to characterise the underlying mechanisms.LocationGlobal.Time period1958–2020.Major taxa studiedAphids.MethodsWe used qualitative and quantitative synthesis techniques to determine whether drought stress has a negative, positive, or null effect on aphid fitness. We examined these effects in relation to 1) aphid biology, 2) the aphid-plant. species combination. We compiled two datasets: 1) a “global” dataset (n = 55 from 55 published studies) comprising one pooled effect size per study, and 2) an “expanded” dataset (n = 93) containing multiple datapoints per study, separated into different measures of aphid fitness but pooled across aphid-plant combinations. Where reported, we extracted data on the effect of drought on plant vigour, and plant tissue concentrations of nutrients and defensive compounds, to capture the potential causes of aphid responses.ResultsAcross all studies (“global” dataset), drought stress had a negative effect on aphid fitness: Hedges’ g = −0.57; 95% confidence interval (CI95) = ±0.31. The “expanded” dataset indicated that, on average, drought stress reduced aphid fecundity (g = − 0.98; CI95 = ±0.50) and increased development time (g = 1.13; CI95 = ±1.02). Furthermore, drought stress had a negative impact on plant vigour (g = −7.06; CI95 = ±2.86) and increased plant concentrations of defensive chemicals (g = 3.14; CI95 = ±3.14).Main conclusionsAphid fitness is typically reduced under drought, associated with reduced plant vigour and increased chemical defence in drought-stressed plants. We propose a conceptual model to predict drought effects on aphid fitness in relation to plant vigour and defence.

Present status of fish farming and pond conditions from Basti and Gonda districts, Uttar Pradesh

Fish ponds operate as an open ecological system where natural and technological processes are built on one another and are implemented in a non-separable way. Pond fish farms contribute to preserve biodiversity. In both districts the composite fish culture technology is commonly followed for fish farming with six species combination i.e. Indian Major Carps (IMC) i.e. Catla, Rohu and Mrigal (Nain) and Exotic Major Carps (EMC) i.e. Silver carp, Grass carp and Common carp. There are 14 blocks in Basti district in which 3848 number of ponds are found. These ponds cover 1040.42 ha of water spread area. There are 16 blocks in Gonda district. The number of ponds is 4471 with water spread area of 3706.86 ha. The total productions of fishes are 1800 ton/year in Basti district while 3850 ton/year in Gonda district. The average productions are 2800 kg/ha/ year and 3000 kg/ha/year in Basti and Gonda districts, respectively. The data indicated that the Gonda district have more potential in fish production compared to Basti district. The maximum ponds were of less than 1 hectare in both districts. The respondents were 68% in Basti district and 76% in Gonda District. 82% and 70% respondents have leased pond in Basti and Gonda districts, respectively. Gonda district has more potential for fishing in future.

Classification of boreal larch forests of the continental sector of Northern Eurasia (Conspectus of Syntaxa)

The analysis of modern state of boreal larch forests in their main part of range placed in continental bioclimatic sector of Northern Eurasia (Siberia and continental part of Russian Far East) was performed. Conspectus of larch forests syntaxa was developed and it includes one class - Vaccinio myrtilli-Piceetea abietis Br.-Bl. in Braun-Blanquet et al. 1939, one subclass - Laricenea cajanderi-sibiricae subclass nova hoc loco, two orders - Ledo-Laricetalia cajanderi Ermakov in Ermakov et Alsynbayev 2004, Lathyro humilis-Laricetalia cajanderi Ermakov, Cherosov et Gogoleva 2002, six alliances - Ledo palustris-Laricion cajanderi Ermakov in Ermakov et Alsynbayev 2004, Pino sibiricae-Laricion sibiricae Ermakov in Ermakov et Alsynbayev 2004 (syn. Pino sibiricae-Laricion sibiricae Guinochet ex Dostalek et al. 1988 nom. nud., art. 2b, art. 8, Barkman et al., 1976, art. 2b, art. 8, Weber et al., 2000), Cladonio stellaris-Laricion gmelinii Anenkhonov et Chytry 1998, Empetro-Piceion obovatae Morozova in Morozova et al. 2008, Aulacomnio acuminati-Laricion cajanderi Ermakov Cherosov et Gogoleva 2002, Rhododendro daurici-Laricion gmelinii Ermakov in Krestov et al. 2009 and 30 associations. Diagnostic features of all syntaxa and their main ecological characteristics were represented. The problems of larch forests classification and syntaxa nomenclature were discussed. All diversity of boreal light-coniferous deciduous (larch) forests of continental bioclimatic sector of Northern Eurasia of the class Vaccinio-Piceetea was included in new subclass Laricenea cajanderi-sibiricae subclass nova hoc loco. Diagnostic species combination of the subclass includes predominating larch species ( Larix cajanderi, L. sibirica, L. gmelinii, L. decidua, L. olgensis ) and diagnostic species of the subordinated orders Ledo-Laricetalia cajanderi and Lathyro humilis-Laricetalia cajanderi .

Varied Effects of Tending Ant Species on the Development of Facultatively Myrmecophilous Lycaenid Butterfly Larvae

Ants often tend and protect the larvae of various myrmecophilous lycaenid species, which influences the fitness of butterflies by altering their growth and developmental time. Tending produces diverse effects depending on lycaenid sex and the lycaenid/ant species combination. Effects are widely variable, especially in facultatively myrmecophilous lycaenids such as Plebejus argyrognomon praeterinsularis, because they are associated with several ant species and can survive without any ant tending. We studied the effects of ant tending on the adult body mass and larval developmental time of P. argyrognomon praeterinsularis. Female larvae grew significantly heavier as adults when tended by Camponotus japonicus rather than by either Lasius japonicus or no ant species. Ant tending did not affect the body mass of adult males or the developmental time of either male or female larvae. Thus, tending by C. japonicus could increase the fitness of P. argyrognomon praeterinsularis by increasing the mass of females without prolonging the duration of vulnerable immature stages, because larger females generally lay more eggs. This means that even facultatively myrmecophilous lycaenids might gain fitness benefits from particular ant species, which could be important in the conservation and management of at-risk species of facultatively myrmecophilous lycaenids.

1186. Prevalence of Carbapenemase-Producing Enterobacteriaceae (CPE) in Hospital Drains in Southern Ontario

Background Hospital waste water systems are an emerging reservoir for CPE. We aimed to describe the prevalence of CPE in hospital drains in southern Ontario, where patients are rarely colonized/infected by CPE. Methods Ten Ontario hospitals identified rooms occupied by CPE+ inpatients from 2007 to 2017. Drain swabs from patient rooms and communal shower rooms were inoculated into BHI + 10% Dey-Engley neutralizing broth and incubated overnight, then PCR on enriched broth for carbapenemase genes as well as culture on McPOD/McMEM were performed. Results Over 10 years in 10 hospitals, 343 CPE+ inpatients exposed 1,205 drains (852 sinks, 353 bathtub/shower drains) in 501 patient rooms and 71 communal shower rooms. 53 (4%) drains in 40 (8%) patient rooms and 10 (14%) communal shower rooms were CPE+ by PCR and culture. CPE+ drains were from 15/475 (3%) hand hygiene sinks, 4/352 (1%) bathroom sinks, 23/272 (9%) bathtubs/showers, and 11/81 (13.6%) communal showers. Eleven (21%) of the CPE+ drains contained 31 CPE gene/species combinations. Patient room drain CPE gene/species combinations are shown in Figure 1: eight (15%) matched the CPE gene/species combination of a room occupant, 23 (43%) matched gene only, and 23 (43%) did not match. 54% of drain isolates were Enterobacter spp. but 9% of patient isolates were Enterobacter spp. There were 155 (13%) additional drains with one or more genes detected by PCR but not culture; 94 (61%) contained VIM (88 bathtub, one bathroom sink, and five hand hygiene sink drains), 33 GES, 17 OXA, 16 IMP, 10 KPC, and five NDM. There were six drains where one or more genes were detected by culture but not PCR; four (67%) were bathtub/shower drains containing an OXA, one bathtub/shower drain containing an NDM, and one hand hygiene sink drain containing a KPC. Conclusion Hospital drains may become a reservoir for CPE, which may persist for years. Sensitivity of PCR and culture for detection of CPE and CP organisms may differ. The presence of “unmatched” drains suggests undetected patient colonization. Risk of transmission from drains to room occupants requires investigation. Disclosures All authors: No reported disclosures.