Whole Genome Resources of 17 Curtobacterium flaccumfaciens Strains Including Pathotypes of C. flaccumfaciens pv. betae, C. flaccumfaciens pv. oortii and C. flaccumfaciens pv. poinsettiae

Curtobacterium flaccumfaciens complex species in the family Microbacteriaceae encompasses a group of plant pathogenic actinobacterial strains affecting annual crops and ornamental plants. The species includes five pathovars namely C. flaccumfaciens pv. betae, C. flaccumfaciens pv. flaccumfaciens, C. flaccumfaciens pv. ilicis, C. flaccumfaciens pv. oortii, and C. flaccumfaciens pv. poinsettiae. Despite the economic importance of C. flaccumfaciens, its members have rarely been investigated for their phylogenetic relationships, molecular characteristics and virulence repertories due in part to the lack of whole genome resources. Here we present the whole genome sequence of 17 C. flaccumfaciens strains representing members of four pathovars isolated from different plant species in a diverse geographical and temporal span. The genomic data presented in this study will pave the way of research on the comparative genomics, phylogenomics and taxonomy of C. flaccumfaciens, and extend our understanding of the virulence features of the species.

Plant age at the time of ozone exposure affects flowering patterns, biotic interactions and reproduction of wild mustard

Exposure of plants to environmental stressors can modify their metabolism, interactions with other organisms and reproductive success. Tropospheric ozone is a source of plant stress. We investigated how an acute exposure to ozone at different times of plant development affects reproductive performance, as well as the flowering patterns and the interactions with pollinators and herbivores, of wild mustard plants. The number of open flowers was higher on plants exposed to ozone at earlier ages than on the respective controls, while plants exposed at later ages showed a tendency for decreased number of open flowers. The changes in the number of flowers provided a good explanation for the ozone-induced effects on reproductive performance and on pollinator visitation. Ozone exposure at earlier ages also led to either earlier or extended flowering periods. Moreover, ozone tended to increase herbivore abundance, with responses depending on herbivore taxa and the plant age at the time of ozone exposure. These results suggest that the effects of ozone exposure depend on the developmental stage of the plant, affecting the flowering patterns in different directions, with consequences for pollination and reproduction of annual crops and wild species.

The Biology of Canadian Weeds. xxx. Capsella bursa-pastoris (L.) Medik.

<i>Capsella bursa-pastoris</i> (L.) Medik, shepherd’s purse, is a cosmopolitan summer or winter annual weed species distributed throughout temperate and subtropical regions of the world and is considered one of the most common plants on earth. It is an opportunistic annual that colonizes newly disturbed, open or dry environments and is ubiquitous in cultivated lands in Canada. In annual crops in western Canada, <i>C. bursa-pastoris</i> has been among the 20 most abundant weeds since the first weed surveys in 1970. It is most easily distinguished by its small white four-petalled flowers and its heart-shaped seed-pods, but exhibits considerable variation in leaf shape and flowering time. It has been used for food and medicine by numerous cultures. Its golden-brown seeds are produced in large numbers predominantly through self-pollination and can form a substantial seed bank, with reported values ranging to several hundred thousand seeds m^-2. While seeds usually disperse near the mother plant, long-distance dispersal by attaching to vehicles, people and other vectors may be facilitated by its mucilaginous coat. <i>Capsella bursa-pastoris</i> does not produce fertile hybrids with other species of economic or ecological significance. It is generally well controlled by soil-applied and foliar (post-emergence) herbicides although its presence in agricultural fields may result in substantial yield loss, as documented in cole crops in North America and grain crops in Europe. The species can host a wide range of insect, nematode, fungal, viral, and bacterial pests that may damage crop species.

Effect of the Different Soil Types on Chrysanthemum Cut Flower Quality

Cultivating annual crops in the high upland has the potential to increase avalanche and land erosion. Therefore, chrysanthemum extensification from high upland to medium upland can create sustainable agriculture. The differences between high upland and medium upland are microclimate and soil type. Meanwhile, the effect of soil type between the high upland and the medium upland on the chrysanthemum spray type quality is unknown. The study aimed to determine the effect of different soil types on the quality of chrysanthemums when planted in high upland. The study used a split plot design with two factors. The first factor was the type of soil, such as Andosol from the high upland and Latosol from the medium upland. The second factor was the chrysanthemum varieties, such as Yastayuki (white flower), Arosuka Pelangi (yellow flower) and Socakawani (red flower). The results showed that both Andosol and Latosol soil types could produce the same quality of chrysanthemum in all varieties when planted in high upland. The quality aspects of chrysanthemum were the plant height, the stem diameter, the number of flowers and flower color. Consequently, we could extend the cultivation of chrysanthemum in medium upland by using Latosol type soil.

QTL Map of Early- and Late-Stage Perennial Regrowth in Zea diploperennis

Numerous climate change threats will necessitate a shift toward more sustainable agricultural practices during the 21st century. Conversion of annual crops to perennials that are capable of regrowing over multiple yearly growth cycles could help to facilitate this transition. Perennials can capture greater amounts of carbon and access more water and soil nutrients compared to annuals. In principle it should be possible to identify genes that confer perenniality from wild relatives and transfer them into existing breeding lines to create novel perennial crops. Two major loci controlling perennial regrowth in the maize relative Zea diploperennis were previously mapped to chromosome 2 (reg1) and chromosome 7 (reg2). Here we extend this work by mapping perennial regrowth in segregating populations involving Z. diploperennis and the maize inbreds P39 and Hp301 using QTL-seq and traditional QTL mapping approaches. The results confirmed the existence of a major perennial regrowth QTL on chromosome 2 (reg1). Although we did not observe the reg2 QTL in these populations, we discovered a third QTL on chromosome 8 which we named regrowth3 (reg3). The reg3 locus exerts its strongest effect late in the regrowth cycle. Neither reg1 nor reg3 overlapped with tiller number QTL scored in the same population, suggesting specific roles in the perennial phenotype. Our data, along with prior work, indicate that perennial regrowth in maize is conferred by relatively few major QTL.

Shaping the Brazilian landscape: a process drive by land occupation, large-scale deforestation, and rapid agricultural expansion

Brazil is one of the largest food producers in the world, a leading role that prompted a profound process of anthropization of itslandscapes. Knowing the dynamics and dimension of these transformations is essential for a more efficient and sustainable useof the country’s natural resources. Thus, in this study we present, based on an unprecedented sample design and interpretationof 85,152 sample points in Landsat images, the area estimates of the main land cover and land use classes in Brazil, as wellas their annual transitions, from 1985 to 2018. Our results indicate that, of the 850 Mha that comprise the national territory,294.2 Mha±1.44%were anthropized in 2018, with ~34%of this area converted after 1985. In this period, there was a loss of98.2 Mha±2.27%of natural vegetation, and an increase of 55.1 Mha±0.64%in the pasture areas and 28.2 Mha±0.29%in theareas of annual crops. The transition analysis showed that 83.07 Mha±1.31%of pastures and 9.64 Mha±0.45%of agriculture(annual, semi-perennial, and perennial combined) occurred over natural vegetation, 18.12 Mha±0.63%of pastures wereconverted to agriculture, while another 9.7 Mha±0.45%were abandoned, which can serve as important land reserves for otheruses. The vast public dataset, approaches (simple, robust, and straightforward), codes and tools (open and available) utilizedin this study can be easily employed in any other region of the world, in support of environmental monitoring and improvedterritorial governance practices.

Productivity and Profitability Assessment of Lemon Based Agroforestry Systems in Bangladesh

A field experiment was conducted from May 2017 to February 2018 at the research farm of Bangabandhu Sheikh Mujibur Rahman Agricultural University to evaluate the performance and profitability of three seasonal (Broccoli, Cabbage and Okra) and two annual crops (ginger and turmeric) in lemon-based agroforestry systems. The experiment was laid out in a Randomized Complete Block Design (RCBD) and replicated thrice. For seasonal crops the treatments were sole field (T0), 50 cm distance from tree base (DTB) with ginger (T1), 50 cm DTB with turmeric (T2), 100 cm DTB with ginger (T3) and 100 cm DTB with turmeric (T4). For annual crops (ginger and turmeric) the treatments were sole field (T0) and four distance regimes (50, 100, 150 and 200 cm) from the lemon tree base in agroforestry systems. The results of the study revealed that the yield of seasonal crops decreased and the yield of annual crops and perennial trees increased in agroforestry than respective sole cropping systems. The yield performance of crops component was significantly decreased with the decreasing distance towards tree base in agroforestry systems. The economic analysis showed that the net return, benefit-cost ratio (BCR) and land equivalent ratio (LER) was higher in the lemon-based agroforestry system than sole cropping. Therefore, the cultivation of cabbage, broccoli, okra, ginger and turmeric under lemon-based agroforestry systems are economically profitable.