Epichloë Fungal Endophytes Influence Seed-Associated Bacterial Communities

Seeds commonly harbour diverse bacterial communities that can enhance the fitness of future plants. The bacterial microbiota associated with mother plant’s foliar tissues is one of the main sources of bacteria for seeds. Therefore, any ecological factor influencing the mother plant’s microbiota may also affect the diversity of the seed’s bacterial community. Grasses form associations with beneficial vertically transmitted fungal endophytes of genus Epichloë. The interaction of plants with Epichloë endophytes and insect herbivores can influence the plant foliar microbiota. However, it is unknown whether these interactions (alone or in concert) can affect the assembly of bacterial communities in the produced seed. We subjected Lolium multiflorum plants with and without its common endophyte Epichloë occultans (E+, E-, respectively) to an herbivory treatment with Rhopalosiphum padi aphids and assessed the diversity and composition of the bacterial communities in the produced seed. The presence of Epichloë endophytes influenced the seed bacterial microbiota by increasing the diversity and affecting the composition of the communities. The relative abundances of the bacterial taxa were more similarly distributed in communities associated with E+ than E- seeds with the latter being dominated by just a few bacterial groups. Contrary to our expectations, seed bacterial communities were not affected by the aphid herbivory experienced by mother plants. We speculate that the enhanced seed/seedling performance documented for Epichloë-host associations may be explained, at least in part, by the Epichloë-mediated increment in the seed-bacterial diversity, and that this phenomenon may be applicable to other plant-endophyte associations.

Cytogenetic characteristics of seed progeny of old-aged trees of Pinus pallasiana and Picea abies (Pinaceae)

Information on cytogenetic changes in the seed offspring of old-aged trees is insufficient and inconsistent. In our studies, 150–200-year old trees of Picea abies and Pinus pallasiana were used. We analyzed peculiarities of their karyotype, nucleus-forming region, and nucleolus in the cells of seedlings of P. abies and P. pallasiana emerged from seeds in natural populations and plantations of introduced plants. As a result, age-dependent cytogenetic disorders were observed, such as the chromosome bridges, lag, premature segregation, and agglutination. Peculiarities with regard to number and structure of secondary chromosome constriction are demonstrated. The identified properties of the cell structure of seeds of old-aged trees of P. abies and P. pallasiana indicate that more resources are needed to maintain their protein synthesis at a normal level. The increased number of abnormalities indicates a significant impact of accumulated intracellular metabolites and cytopathological phenomena in mother plants on the quality of seed offspring.

EMPIRICAL USE OF THREE OAK SPECIES IN AFFORESTATION: LESSONS FROM SOWING AND TRANSPLANTING EXPERIMENTS

The effects of different factors on the growth in height and diameter of oak saplings in comparative cultures were estimated: progeny from autumn and spring sowing of acorns (1); growing conditions of pedunculate oak (Quercus robur L.) mother plants (2); the initial planting density of sessile oak (Q. petraea Liebl.) (3); natural lightening level of downy oak (Q. pubescens Willd.) mother plants (4). The pedunculate oak seedlings obtained after spring sowing were characterized by faster growth compared with those obtained from the autumn sowing. The lower growth rate observed in seedlings sown in autumn was due to the prolonged frosty weather during winter, which led to a decrease in acorn viability and progeny vigour. Due to the higher genetic diversity of the progeny obtained from the free-pollinated pedunculate oaks, it is possible that their growth was more intense and stable in comparison to those of saplings obtained from the acorns of isolated trees. The planting under the forest canopy had a clear influence on the growth in height of saplings. At low density levels (1.0 x 1.0 m), the sessile oak saplings benefited from larger availability of soil nutrients and displayed the highest growth, contrasting with those planted at high density (0.5 x 0.5 m). The deep and moderate shading caused a substantial reduction in the growth of downy oak saplings. Therefore, when planting, it is recommended to avoid using fast-growing species, which, due to asymmetric competition, could drastically reduce the growth in height of the downy oak saplings. Prolonged regeneration of the pruned root system following the transplantation process of sessile and downy oak seedlings determined their very slow growth in the first years of life.

Genetic Identity, Diversity, and Population Structure of the Sweetpotato's (I. batatas) Germplasm Collection From International Potato Center's

The in trust sweetpotato collection housed by the International Center of Potato (CIP) is one of the largest assemblages of plant material representing the genetic resources of this important staple crop. The collection currently contains almost 6,000 accessions of Ipomoea batatas (cultivated sweetpotato) and over 1,000 accessions of sweetpotato crop wild relatives (CWRs). In this study, the entire cultivated collection (5,979 accessions) was genotyped with a panel of 20 simple sequence repeat (SSR) markers to assess genetic identity, diversity, and population structure. Genotyping and phenotyping of in vitro plantlets and mother plants were conducted simultaneously on 2,711 accessions (45% of the total collection) to identify and correct possible genetic identity errors which could have occurred at any time over the thirty plus years of maintenance in the in vitro collection. Within this group, 533 accessions (19.6%) had errors in identity. Field evaluations of morphological descriptors were carried out to confirm the marker data. A phylogenetic tree was constructed to reveal the intraspecific relationships in the population which uncovered high levels of redundancy in material from Peru and Latin America. These genotypic data were supported by morphological data. Population structure analysis demonstrated support for four ancestral populations with many of the accessions having lower levels of gene flow from the other populations. This was especially true of germplasm derived from Peru, Ecuador, and Africa. The set of 20 SSR markers was subsequently utilized to examine a subset of 189 accessions from the USDA sweetpotato germplasm collection and to identify and reconcile potential errors in the identification of clones shared between these collections. Marker analysis demonstrated that the USDA subset of material had 65 unique accessions that were not found in the larger CIP collection. As far as the authors are aware, this is the first report of genotyping an entire sweetpotato germplasm collection in its entirety.

Resistance to post-emergent herbicides is becoming common for grass weeds on New Zealand wheat and barley farms

To estimate the prevalence of herbicide-resistant weeds, 87 wheat and barley farms were randomly surveyed in the Canterbury region of New Zealand. Over 600 weed seed samples from up to 10 mother plants per taxon depending on abundance, were collected immediately prior to harvest (two fields per farm). Some samples provided by agronomists were tested on an ad-hoc basis. Over 40,000 seedlings were grown to the 2–4 leaf stage in glasshouse conditions and sprayed with high priority herbicides for grasses from the three modes-of-action acetyl-CoA carboxylase (ACCase)-inhibitors haloxyfop, fenoxaprop, clodinafop, pinoxaden, clethodim, acetolactate synthase (ALS)-inhibitors iodosulfuron, pyroxsulam, nicosulfuron, and the 5-enolpyruvyl shikimate 3-phosphate synthase (EPSPS)-inhibitor glyphosate. The highest manufacturer recommended label rates were applied for the products registered for use in New Zealand, often higher than the discriminatory rates used in studies elsewhere. Published studies of resistance were rare in New Zealand but we found weeds survived herbicide applications on 42 of the 87 (48%) randomly surveyed farms, while susceptible reference populations died. Resistance was found for ALS-inhibitors on 35 farms (40%) and to ACCase-inhibitors on 20 (23%) farms. The number of farms with resistant weeds (denominator is 87 farms) are reported for ACCase-inhibitors, ALS-inhibitors, and glyphosate respectively as: Avena fatua (9%, 1%, 0% of farms), Bromus catharticus (0%, 2%, 0%), Lolium spp. (17%, 28%, 0%), Phalaris minor (1%, 6%, 0%), and Vulpia bromoides (0%, not tested, 0%). Not all farms had the weeds present, five had no obvious weeds prior to harvest. This survey revealed New Zealand’s first documented cases of resistance in P. minor (fenoxaprop, clodinafop, iodosulfuron) and B. catharticus (pyroxsulam). Twelve of the 87 randomly sampled farms (14%) had ALS-inhibitor chlorsulfuron-resistant sow thistles, mostly Sonchus asper but also S. oleraceus. Resistance was confirmed in industry-supplied samples of the grasses Digitaria sanguinalis (nicosulfuron, two maize farms), P. minor (iodosulfuron, one farm), and Lolium spp. (cases included glyphosate, haloxyfop, pinoxaden, iodosulfuron, and pyroxsulam, 9 farms). Industry also supplied Stellaria media samples that were resistant to chlorsulfuron and flumetsulam (ALS-inhibitors) sourced from clover and ryegrass fields from the North and South Island.

Screening of Mango Landraces for Polyembryony and Confirmation of Seedling Origin using Microsatellite Markers

Background: The introduction of polyembryonic rootstocks in the area of propagation is of great importance since they produce one zygotic and several nucellar plantlets. Proper identification of sexual embryo from each hybrid seed is necessary in order to preserve only the nucellar seedlings, which would help to maintain the rootstock’s genetic characteristics as well as to overcome the major constraints in the area of fruit breeding especially in hybridization programme by eliminating the nucellar ones to advanced generations. Contrasting reports exists regarding the vigour of zygotic seedlings of polyembryonic mango genotypes. It is necessary to identify/ distinguish the zygotic seedling from the nucellar population at an early stage, for which, microsatellite analysis could be a reliable tool. Methods: The experiment was laid out in completely randomized design (CRD) with 20 treatments replicated thrice. The twenty local mango landraces from Thiruvananthapuram (Kerala) were screened for polyembryony and were geo-referenced. Germination studies were conducted. Microsatellite analysis of all the plantlets from two varieties which exhibited the highest polyembryony were done using SSR primers and their banding patterns were compared with those of their respective mother plants. Result: Out of twenty mango varieties screened, seventeen were polyembryonic. Kappa Manga recorded the highest germination, germination index and seedling vigour index-I. Kotookonam Varikka recorded the highest polyembryony and followed by Kochu Kilichundan. Microsatellite analysis revealed that all the seedlings obtained from the respective stones of Kotookonam Varikka and Kochu Kilichundan had identical SSR profile to the mother plant, which indicated nucellar origin of seedlings having similar genetic composition to the mother plant.

Brussels sprouts seeds growing without mother plants transplanting in the conditions of the Moscow region

В течение 2019–2021 годов на опытно-производственной базе ФГБНУ ВНИИФ в Московской области (Одинцовский городской округ) выращивали растения капусты брюссельской сорта Геркулес 1342 для получения семян в беспересадочной культуре без применения химически синтезированных препаратов защиты растений и агрохимикатов. Беспересадочный способ позволил вырастить семена капусты брюссельской исключив основные, наиболее затратные и трудоемкие агротехнические мероприятия: отбор и уборка с поля маточных растений с корневой системой, перевозка в хранилище и хранение маточников при соблюдении режима хранения, зачистка маточников и весенняя подготовка к высадке, высадка маточников в открытый грунт. После высадки в поле и приживания маточных растений потери могут достигать 50%. В беспересадочной культуре сохранность семенных растений после перезимовки составляла 80%, а семенная продуктивность достигала 23 г с одного растения, при лабораторной всхожести – 98%, что значительно превосходит контрольный вариант – выращивание семян в пересадочной культуре. Растения, выращенные из семян, полученных в беспересадочной культуре, склонности к преждевременному цветению не проявляли и формировали нормальные, по морфологическим признакам, продуктивные растения. Семенные растения капусты брюссельской сорта Геркулес 1342 успешно переживали в открытом грунте без укрытия как малоснежную зиму 2020 года, так и зиму 2021 года с достаточно высоким снежным покровом – до 55 см. При этом растения имели незначительные повреждения не от мороза, а от мышей. В отличие от маточных растений, высаживаемых в открытый грунт, после зимнего хранения, маточные растения, выращенные в беспересадочной культуре, не имели повреждения точек роста вследствие солнечных ожогов. Таким образом сохранялось наиболее продуктивное первое цветение. During 2019–2021, Brussels sprouts of the Hercules 1342 cultivar were grown at the experimental production base of the FSBSI VNIIF in the Moscow region, Odintsovo District in order to obtain seeds in a non-planting culture without the use of chemically synthesized plant protection preparations and agrochemicals. The non-planting method made it possible to grow Brussels sprouts seeds by eliminating the main, most expensive and time-consuming agrotechnical measures: selection and cleaning of mother plants with a root system from the field, transportation to the storage and storage of mother plants while observing the storage regime, cleaning of mother plants and spring preparation for planting, planting in the open ground. After planting in the field and taking root of the mother plants, losses can reach 50%. In a seedless culture, the safety of seed plants after overwintering was 80%, and the seed productivity reached 23 grams per plant, with laboratory germination – 98%, which significantly exceeds the control variant: growing seeds in a transplant culture. Plants grown from seeds obtained in a non-planting culture did not show a tendency to premature flowering and formed normal ones. According to morphological characteristics, productive plants. Seed plants of Brussels sprouts of the Hercules 1342 cultivar successfully survived both the low – snow winter of 2020 and the winter of 2021 with a sufficiently high snow cover-up to 55 cm in the open ground without shelter. At the same time, the plants had minor damage not from frost, but from mice. Unlike the mother plants planted in the open ground, after winter storage, the mother plants grown in a non-planting culture did not have damage to the growth points due to sunburn. Thus, the most productive first flowering was preserved.

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.

Phenotypic plasticity in plant defense across life stages: Inducibility, transgenerational induction, and transgenerational priming in wild radish

As they develop, many plants deploy shifts in antiherbivore defense allocation due to changing costs and benefits of their defensive traits. Plant defenses are known to be primed or directly induced by herbivore damage within generations and across generations by long-lasting epigenetic mechanisms. However, little is known about the differences between life stages of epigenetically inducible defensive traits across generations. To help fill this knowledge gap, we conducted a multigenerational experiment to determine whether defense induction in wild radish plants was reflected in chromatin modifications (DNA methylation); we then examined differences between seedlings and reproductive plants in current and transgenerational plasticity in chemical (glucosinolates) and physical (trichomes) defenses in this species. Herbivory triggered genome methylation both in targeted plants and their offspring. Within one generation, both defenses were highly inducible at the seedling stage, but only chemical defenses were inducible in reproductive plants. Across generations, herbivory experienced by mother plants caused strong direct induction of physical defenses in their progeny, with effects lasting from seedling to reproductive stages. For chemical defenses, however, this transgenerational induction was evident only in adults. Transgenerational priming was observed in physical and chemical defenses, particularly in adult plants. Our results show that transgenerational plasticity in plant defenses in response to herbivore offense differs for physical and chemical defense and changes across plant life stages.

Fruit Quality Characters of Myrtle (Myrtus communis L.) Selections: Review of a Domestication Process

Interest in myrtle (Myrtus communis L.) by food, cosmetics, and pharmaceutic industries generated the integration of biomasses harvested from wild populations as raw materials with yields of cultivated orchards. The domestication process is reviewed considering shoot, fruit, and leaf biometric characters of selections obtained in three steps of the program. The first step started in Sardinia (Italy) in 1995 by the analysis of wild germplasm variability. Seventy accessions were the object of the first studied population of mother plants. Agamic propagation tests, as well quality evaluations of fruit and leaves, were integrated into the first step. In the second step, a field of comparison of forty-two agamically propagated cultivars functional to biomass production and to food uses was planted and evaluated for phenotypic characters. In the third step, a new population of twenty selections was obtained by open cross-pollination of some of the cultivars and further phenotypic selection in seedling population. In this review, the three populations are compared for biometric shoot, leaves and fruit characters, in order to verify the pressure of domestication process on these traits. Wild populations showed high variability only partially used during the first step, while the hybridization may create new variability for use in the genetic improvement of myrtle.