Damaged Buds Research Articles

Evaluations on Bioecology of Contarinia pruniflorum Coutin & Rambier, 1955 (Diptera: Cecidomyiidae)

Apricot flower midge (Contarinia pruniflorum Coutin & Rambier Diptera: Cecidomyiidae) was first detected in Prunus species in the 1950s and did not become a significant pest for a long time. However, towards the 2000s, the pest caused damage to apricot and plum especially in Mediterranean countries and its distribution continued to increase. The population density of the pest is closely related to the climate of the agricultural area. In recent years, the fluctuation in climatic data causes the population fluctuations. The study was carried out in the Kale and the Yeşilyurt district of Malatya province (Turkey) in 2017-2018. Some biological stages of apricot flower midge were determined in Malatya province and these data were interpreted together with climatic data. It was determined that the pest overwinters as a pupa in the soil. In February, the adult emerges from the pupa with the warming of the air and soil temperatures. It was determined that the adult emerged from the pupa when the soil temperature was 13-14 °C and the air temperature was 7-15 °C. At the beginning of the pink-bud stage of apricot, the pests lay eggs into flower buds. The larval development is approximately 25-28 days. The average number of larvae in the damaged buds was 14, the maximum number of larvae in a bud was 26, and the pest gave an offspring annually and the ratio of male to female was 0.08.

The early bud gets the cold: Diverging spring phenology drives exposure to late frost in a Picea mariana [(Mill.) BSP] common garden.

Under climate change, the increasing occurrence of late frost combined with advancing spring phenology can increase the risk of frost damage in trees. In this study, we tested the link between intra-specific variability in bud phenology and frost exposure and damages. We analysed the effects of the 2021 late frost event in a black spruce (Picea mariana (Mill.) BSP) common garden in Québec, Canada. We hypothesised that the timing of budbreak drives the exposure of vulnerable tissues and explains differences in frost damage. Budbreak was monitored from 2015 to 2021 in 371 trees from five provenances originating between 48° and 53° N and planted in a common garden at 48° N. Frost damages were assessed on the same trees through the proportion of damaged buds per tree and related to the phenological phases by ordinal regressions. After an unusually warm spring, minimum temperatures fell to -1.9°C on May 28 and 29, 2021. At this moment, trees from the northern provenances were more advanced in their phenology and showed more frost damage. Provenances with earlier budbreak had a higher probability of damage occurrence according to ordinal regression. Our study highlights the importance of intra-specific variability of phenological traits on the risk of frost exposure. We provide evidence that the timings of bud phenology affect sensitivity to frost, leading to damages at temperatures of -1.9°C. Under the same conditions, the earlier growth reactivation observed in the northern provenances increases the risks of late frost damage on the developing buds.

Seasonal incidence of major insect pests of jasmine Jasminum sambac L

Jasmine Jasminum sambac L. is an important ornamental crop that fetches recurrent income to farmers. The present study was carried out in three locations Sevandhanagar, Navalurkuttappattu and Horticulture farm, TNAU, Tiruchirappalli, Tamil Nadu, India from August 2019 to September 2020. The seasonal incidence of major insect pests such as Hendecasis duplifascialis Hampson, Nausinoe geometralis Guenee, Contarinia maculipennis Felt, Frankliniella scultzei Trybom and Tetranychus urticae Koch were studied. Hendecasis duplifascialis incidence was observed to be maximum (31.63% damaged buds) in second fortnight of October in Sevandhanagar; in Navalurkuttappattu, it was the incidence of N. geometralis (2.2 webs/ plant) that was maximum, and noticed in the second fortnight of December. In horticulture farm, maximum damage was of C. maculipennis (48.66% damaged buds) noticed in the second fortnight of September. Thrips population was significant and was observed positively correlated with maximum temperature in Sevandhanagar (r = 0.55).

The Eurasian strawberry blossom weevil, Anthonomus rubi (Herbst, 1795), is established in North America

AbstractWe report the strawberry blossom weevil, Anthonomus rubi (Herbst, 1795) (Coleoptera: Curculionidae), a species native to Europe, Asia, and North Africa, as established in British Columbia, Canada. This is the first report of A. rubi in North America. We provide a diagnosis of the species and compare it with other species of the genus Anthonomus Germar in Canada. This species is a pest of plants in Rosaceae Jussieu, including economically important berries such as strawberries (Fragaria Linnaeus) and raspberries (Rubus idaeus Linnaeus), and of native berries of importance to Indigenous peoples in Canada. Female weevils oviposit eggs inside developing flower buds and sever flower stalks, facilitating larval development inside damaged buds and thus reducing fruit yields. Surveys to confirm the presence of A. rubi conducted in 2020 found the weevil to be well established in cultivated and wild hosts throughout the Greater Vancouver area and Fraser Valley, British Columbia. At least one species of parasitoid wasp in the genus Pteromalus Swederus (Hymenoptera: Pteromalidae) has been found in association with A. rubi in the province. Future investigations are required to understand the biology of A. rubi in its new range, assess its impact on berries, and develop management strategies.

Determination of Cold Resistance of Buds and Flowers on Kütahya Sour Cherry Cultivar

This study was carried out in 2018 in order to determine the resistance of flower buds and flowers to low temperatures in winter and spring periods in Kutahya sour cherry cultivar, in Konya’s conditions. In order to determine the temperature of the flower buds and flowers, the samples taken at different periods were gradually placed in the temperature-lowered cabinet and tested. The buds were tested, held at temperatures between 0 and -22 o C. After the application, 70% or above of damaged buds were considered dead. In addition, total, bound and free water, dry matter, total carbohydrate, protein, proline and nutrient levels were determined. Differences between the mortality rates of buds and flowers at different temperatures were statistically significant. In the winter season, buds with high frost resistance started to lose this resistance towards the spring season. Temperatures of more than 50% of buds are observed at -16°C on 29.01; 20.02 and 06.03 at -15°C; 20.03 at -11°C; it was determined as -10°C on 05.04 and 20.04. According to this, in the city center of Konya cherry flower buds are damaged by frost until the end of March and the probability of damage after this period is reduced. With the emergence of winter season, the water content of the buds has increased significantly. A rapid decrease in the amount of bound water was found in the buds with the emergence of winter and a rapid increase in the amount of free water. On the other hand, the dry matter contents remained stable between 29.01 and 05.03, and a rapid increase occurred on 19.03. The differences between the nutrient amounts were found to be statistically significant. According to this, the content of N in buds has decreased continuously between 29.01 and 20.04. The amounts of P, K, Mn, Zn and S increased from 29.01 to 20.03 and started to decrease after this date. Mg and Fe amounts increased regularly until 20.03 and remained stable after this date. Ca and Cu levels increased until 06.03, then began to fall. The B content increased continuously. The amount of Zn increased regularly until 05.04 and then decreased. S content fluctuated on different dates. Significant differences were determined in terms of carbohydrate content in buds. According to this, the carbohydrate content decreased regularly from 29.01 until 05.04 and started to rise again in 19.04. Bud’s protein contents showed a steady decrease in successive sampling periods. The differences between the contents of the proline were not statistically significant.

Design of Electromagnetic Vibration-Type Single-Bud Sugarcane Seed Metering Device

The objectives of this research were to solve the problem that the existing sugarcane seed metering device had high per cent of damaged seeds and omission rate. An electromagnetic vibration-type single-bud sugarcane seed metering device was designed. It made use of the characteristic of vibrating automatic metering to avoid damaging buds. And it could be adjusted to different sowing speeds by setting the controller. The migratory mechanism was analysed. The helix angle and working parameters of the metering device were obtained by the experiment. The results of the experiment showed that the order of factors affecting the qualification rate was amplitude > frequency > helix angle. The best qualification rate of the metering device was achieved when the helix angle was 6°, the amplitude was 0.4 mm and the frequency was 53.2 Hz, and the results of verification experiments showed that the qualification rate of metering was over 80% and the per cent of damaged buds was 0 with the best parameter combination. This metering device met the standard requirements of sugarcane seeds metering.

CLONAL SELECTION AND SUPERIOR CULTIVAR SELECTION OF IRANIAN GRAPE GERMPLASM TO COLD HARDINESS

Considering the high diversity of grape cultivars and clones in Iran, and also the recent occurrence of extreme cold in the country, varieties and clones of cold tolerant grapes were identified. Cold tolerant cultivars and clones of grape varieties in the collection of grapevines at the Horticulture Research Station of Kahriz in 2005-2007 were studied for severity of damage to cold. The minimum temperature recorded at the Station was -22°C. Four branches (one year old) per plant were selected. Then, the number of healthy and damaged buds was counted after natural and artificial cold treatments. Statistical, cluster and descriptive analyses (coefficient of variation) were performed on the data obtained from clones. Microscopic studies to compare to field observations were performed, and the quantity and quality of fruit was evaluated in the field and laboratory. The results showed that the severity of frost damage in several cultivars was less than in late ripening cultivars. The differences in clones of cultivars were also obvious.

Wielkopąkowiec porzeczkowy – Cecidophyopsis ribis (Westw.), szkodliwość oraz możliwości zwalczania przy użyciu fenpiroksymatu (Ortus 05 SC)

Summary The blackcurrant gall mite (big bud mite) – Cecidophyopsis ribis (Westw.) is the most dangerous pest of blackcurrant in many countries. C. ribis is a key pest in Poland and causes severe damage on some plantations, destroying even more than 50% of the buds. The big bud mite infests most of the commonly grown cultivars and only a few are resistant. Looking for new possibilities to control the pest is still necessary. The experiments were carried out at the Research Institute of Horticulture in 2008–2011. Fenpyroximate active substance in Ortus 05 SC showed high effectiveness in reducing the number of the blackcurrant gall mites emerging from treated buds. Ortus 05 SC (1.25; 1.5 l/ha) and Ortus 05 SC (1.5 l/ha) + Slippa (0.1 l/ha) applied 3 times during migration of the big bud mite, reduced the number of damaged buds by 76–90% compared to the control bush. Also Ortus 05 SC (1.5 l/ha), applied twice: at the beginning and during the full blossom of black currant significantly reduced the number of buds infested by the big bud mite. On the bushes where Ortus 05 SC (1.5 l/ha) + Slippa (0.1 l/ha) were used twice, slightly less damaged buds compared with the treatments without wetting were reported, but the differences were not statistically significant.

Spring occurrence of the strawberry blossom weevil, Anthonomus bisignifer Schenkling on forced strawberry in Nara Prefecture and toxicities of some insecticides to adults

In Nara Prefecture, spring occurrence of bud damage by the strawberry blossom weevil, Anthonomus bisignifer Schenkling, on forced strawberry and wild host plants were investigated. Overwintering adults emerged from hibernation in late March to early April and began to injure flower buds of Rubus hirsutus Thunb. About 2 weeks later, adults injured strawberry flower buds in a greenhouse from early to mid-April. Thereafter until late April, adults began to injure flower buds of Rosa multiflora Thunb. Overwintering adults used different wild host plants depending on the flower budding period. Larval occurrence was earlier on the greenhouse strawberry than on R. hirsutus growing outside of the greenhouse. The start of first generation adults' emergence from the pupae was estimated as about late April to early May. The density of damaged buds on the strawberry differed greatly among years for unknown reasons. Commercial concentrations of thiacloprid, spinosad, and malathion were effective against adults in in vitro experiments.

Evaluation of methods to control Phytonemus pallidus and Anthonomus rubi in organic strawberry production

Abstract: Use of the predatory mite Neoseiulus cucumeris (Oudemans) (Acari, Phytoseiidae) and a fleece cover in combination with pyrethrum application showed potential for control of two important pests in organic production of strawberry (Fragaria × ananassa Duch.), although there were some unexpected interactions between pyrethrum and the release of N. cucumeris that need to be investigated further. Two cultivars, Honeoye and Cavendish, were treated with pyrethrum with or without fleece to control strawberry blossom weevils [Anthonomus rubi Herbst. (Col., Curculionidae)] and N. cucumeris was released to control strawberry mites [Phytonemus pallidus (Banks) (Acari, Tarsonemidae)]. Number of strawberry mites, number of flower buds damaged by the weevil, incidence of grey mould and powdery mildew, and fruit yield were measured in two consecutive fruiting seasons. In Honeoye, the fleece in combination with pyrethrum decreased the proportion of damaged buds by 11–23% and increased yield by 49–91 g per plant. When pyrethrum was used alone it did not influence the number of damaged buds or yield. This indicates that the combined treatment was more effective because of the fleece. In Cavendish, the fleece and pyrethrum treatments were not found to be effective. Almost no P. pallidus was found in Honeoye and the results were not analysable. In plots with Cavendish where N. cucumeris had been released, there were approximately 50% fewer P. pallidus from the end of August onwards in 2003. However, this response did not significantly influence the succeeding year's yield. The number of fruits infected with fungi was very low and no effects were observed for any of the treatments.

EXPRESSÃO DA FERTILIDADE DE GEMAS DA VIDEIRA EM FUNÇÃO DE DIFERENTES ÉPOCAS DE PODA E DOSES DE NITROGÊNIO

Os tratos culturais aplicados ao vinhedo interferem no crescimento vegetativo e reprodutivo de ramos novos da videira. Aépoca de poda e a dose de nitrogênio aplicada antes da brotação natural podem modificar o crescimento vegetativo e a expressão dafertilidade de gemas da videira. Este trabalho teve como objetivo avaliar essa expressão em função de diferentes épocas de poda edoses de nitrogênio. Foi realizada a poda curta hibernal em videiras da cultivar Niagara Rosada, deixando-se nos ramos duas gemas(basal e apical), em três épocas diferentes (precoce, intermediária e tardia), associadas a adubações nitrogenadas com 0, 50 e 100 g de N por planta. Foram avaliados o número de cachos por gema, percentagem de gemas danificadas, percentagem de gemas dormentes, percentagem de inibição de fertilidade de gemas e vigor de ramos novos. O levantamento da fertilidade real foi realizado em laboratório, comparando-se assim com a fertilidade expressa a campo. Para a melhor expressão da fertilidade de gemas verificou-se que a poda intermediária sem adubação nitrogenada e a poda precoce com adubação nitrogenada de 50 g de N por planta estimulou a produção decachos em ramos oriundos da gema basal do ramo podado. A poda tardia com adubação nitrogenada de 100 g de N por plantaestimulou a produção de cachos em ramos oriundos da gema apical do ramo podado.

Variability in the Relationship between Frost Temperature and Injury Level for Some Cultivated Prunus Species

The influence of the species in spring frost sensibility was determined for the Prunus species peach (P. persica (L.) Batsch), sweet cherry (P. avium L.), almond (P. dulcis (Mill.) Webb/P. amygdalus Batsch), japanese plum (P. salicina Lindl.), and blackthorn (P. spinosa L.). The confidence intervals for lethal temperatures of 10% (LT10) and 90% (LT90) bud injury were also determined. In 2000 and 2001, seven frost treatments were made for each one of the phenological stages comprised between B (first swell) and I (jacket split) in two cultivars per each species. The relationships between frost temperature and the proportion of frost damaged buds for each cultivar, year, and phenological stage were adjusted to linear regression models. The 95% confidence intervals were also calculated. The spring frost hardiness order of the species, from the least to most hardy, was as follows: sweet cherry, almond, peach, japanese plum, and blackthorn. Despite the highly homogeneous nature of the frost and bud characteristics, the temperature range for a given injury degree was quite broad, since the confidence interval's breadth for LT10 was as high as about 3 °C and as high as about 6 °C for LT90. Consequently, when critical temperatures are used in making decisions as to when to begin active frost protection, a prudent measure would be to take the temperature references from the upper limits in the confidence intervals.

Temporal dynamics of Otiorhynchus schlaeflini (Coleoptera: Curculionidae) adults and damage assessment on two wine grape cultivars.

The nocturnal temporal dynamics of adults of Otiorhynchus schlaeflini Stierlin on wine grape Vitis vinifelra L. 'Rhoditis' and 'Mavroudi' were studied in the western Peloponnese during spring 1993 and 1994. The maximum number of adults was recorded approximately 3 h after sunset. Emergence began on 13 March 1993 and 19 March 1994; the population peaked on 24 and 16 April in each year, respectively. Low numbers of adults were found during daytime observations in May. The length and the number of knobs, and the number of grapes on twigs from damaged buds were significantly reduced only in 'Rhoditis'. However, the weight of grapes produced on twigs developed from damaged buds was significantly less than those from undamaged buds in both cultivars. We found that the severity of damage caused to buds is dependent on the wine grape cultivar. Therefore, the effect of wine grape cultivar should be taken into account when estimating the economic threshold.

626 Field Assessment of Combined Bud Damage on Floricanes of Red Raspberry Caused by Cold Injury, Clay Colored Weevil, and Spur Blight Disease

A field experiment was conducted in Lynden, Wash., to assess the combined bud damage to raspberry caused by cold injury, clay colored weevil (CCW) and spur blight disease last year. The CCW treatments included 3 and 6 weeks of continuous feedings and a minimal feeding in a nearby planting with no CCW infestation. Two other sets of field experiments evaluated cold injury to raspberry alone. Cold injury caused significant bud damage and moderate yield losses last winter. The large compensatory ability of raspberry makes yield loss due to cold injury alone insignificant in most years. Cold injury reduced berry yield mainly through a drop in lateral number/cane due to bud damage and cane die back. The combined damage of cold injury with infestations of CCW and spur blight, to the buds and fruit yield were devastating, and 60% bud damage and 61% yield loss were recorded. The combined damage was well over the compensatory ability of raspberry, and resulted in not only lower lateral number/cane, but also lower fruit number/lateral and fruit weight. The bud damage by CCW in the spring left little time for the secondary laterals to initiate flowers. An integrated pest management system is highly recommended to avoid the cumulative damage to the buds and has special importance in areas, where cold injury occurs frequently. Bud damage counted as cold injury was higher in the control plots (18%) than in the weevil-infested plots (6% to 9%). This was likely due to undercount of some cold damaged buds in the infested plots, which also suffered CCW feeding. All plots had similar levels of spur blight bud infection numbering from low to mid-teens. Spur blight-infected buds are often capable of producing normal fruiting laterals.

Histological Description of Tarnished Plant Bug (Heteroptera: Miridae) Feeding on Small Cotton Floral Buds

Microscopic features of small cotton floral buds abscised due to Lygus lineolaris (Palisot de Beauvois) feeding and non-insect factors were identified and contrasted with healthy buds. Feeding damage appeared to be most common on staminal columns, developing anthers, and corollas. These tissues exhibited gross enlargement and varying degrees of cellular degradation. Fragmented cell walls were thinner and stained lighter than those that were intact. Desiccation of buds abscised due to Lygus feeding was irregular. Tissues of buds abscised due to non-insect factors stained uniformly and all cells were intact. Uniform basipetal desiccation throughout the bud occurred in non-insect damaged buds, especially in anthers, staminal columns, and carpels. Tissues and cells of healthy buds stained uniformly and consistently and were without structural abnormalities. The biochemical composition of male reproductive tissue of cotton floral buds appears to play an important role in the nutritional physiology of L. lineolaris.

Damage to Young Leaves of Pear Trees by Bryobia rubrioculus (Scheuten) (Acari: Tetranychidae) in Nepal.

Many young leaves of Pharping local pears were injured by a mite pest, Bryobia rubrioculus. Very young leaves sustained severe browning and sometimes withering in an orchard of the Horticulture Development Project, Phase II, in Kirtipur, Nepal. The percentage of damaged buds clearly increased with mite numbers both in Pharping local pear and European pear. On Pharping local pear, the percentage of buds heavily damaged buds reached a plateau of more than 90% when there was an average of ca. 20 mites per bud. Pharping local pear blossomed first, followed by European pear, Ussurian pear and Japanese pear in that order. Since the damage lessened with delay of the bloom, B. rubrioculus is not a serious pest to Japanese pear or Ussurian pear in Kirtipur.

Morphological alterations of Saccharomyces cerevisiae induced by benanomicin A, an antifungal antibiotic with mannan affinity.

The effects of benanomicin A, a mannose-binding antifungal antibiotic, on yeast cells of Saccharomyces cerevisiae were studied by electron microscopy. Cytological studies using vital stain with methylene blue demonstrated that benanomicin A at 20 and 80 microg/ml killed buds in preference to parent cells. In confirmation, examination by TEM revealed that benanomicin A at 80 microg/ml damaged buds more severely than parent cells. The major effect on the ultrastructure was characterized by severe damage to the cell membrane. In addition, it caused expansion and vacuolation of the endoplasmic reticulum (ER), and partial fragmentation and disappearance of nuclear membranes. The membrane-disruptive activity of benanomicin A may be closely associated with its membrane affinity.

Effect of ecdysteroid UDP-glucosyltransferase gene deletion on efficacy of a baculovirus against Heliothis virescens and Trichoplusia ni (Lepidoptera: Noctuidae).

Laboratory, greenhouse, and field studies were conducted to characterize the biological activity of a genetically altered form of Autographa californica (Speyer) nucleopolyhedrosis virus (AcNPV). The altered baculovirus (vEGTDEL) had a deletion in the ecdysteroid UDP-glucosyltransferase gene. Results from bioassays conducted with neonate and 3rd-instar tobacco budworm, Heliothis virescens (F.), as well as with 3rd-instar cabbage looper, Trichoplusia ni (Hübner), showed vEGTDEL caused larval death slightly, but significantly, quicker than AcNPV. Based on supposition (LT50 values were not calculated), it appeared that larval mortality occurred 0.5-1.0 d faster following exposure to vEGTDEL versus AcNPV. Greenhouse studies conducted against H. virescens on cotton showed that hastened virulence exhibited by vEGTDEL led to improved plant protection versus AcNPV. For example, following 5 weekly sessions of foliar application and H. virescens artificial infestation, cotton treated with wettable powder formulations of vEGTDEL or AcNPV at 2.5 x 10(12) OB/ha averaged 25.7 and 61.8% damaged flower buds, respectively. Although vEGTDEL tended to provide more consistent control of T. ni than AcNPV in greenhouse and field trials conducted on leafy vegetables, differences in efficacy between the 2 baculoviruses were marginal and usually not statistically significant. Generally, results from these studies suggest that genetic modification of NPVs to hasten their lethal effect may be a promising strategy for improving the insecticidal properties of the insect-specific pathogens.

GALL MIDGES, CONTARINIA AGRIMONIAE FELT AND DASINEURA SPP. (DIPTERA: CECIDOMYIIDAE), ASSOCIATED WITH BLACKBERRY FLOWER INJURIES AND NUBBINS

Larvae of Contarinia agrimoniae Felt, a gall midge, were discovered during 1986 in blossoms of blackberry cultivars and wild-growing plants that had a history of poor fruit set and `nubbin' formation (Stiles, Semtner, and Reed, 1996). Other species damage blackberries in Europe, but the only North American recognition of Rubus flower bud infestation was with Dasineura rubiflorae Felt during 1886 (Gagne, 1989). During 1995 we found larvae of a Dasineura spp. in damaged buds at two, widely separated, commercial, North Carolina, blackberry sites. It is not known if the latter insects are different from the species that was collected during 1886. Midge larvae probably overwinter in soil under affected plants so we sprayed diazinon on the soil surface before bloom to kill larvae or interfere with pupation and reduce crop injuries. Infested `Shawnee' and `Cheyenne' buds were ≈100% more numerous among controls than diazinon-treated plots. Numbers of larvae varied among infested buds; 83 were observed in one bud from a nontreated `Cheyenne' plot.

An Analysis of Nocturnal Cooling and Frost Damage in Tea Plants in Complex Terrain Using Micro-scale Topographic Factors

Effects of micro-scale topography on near dawn temperature distributions in a complex terrain were examined using micro-scale topographic factors, which calculated with 25m or 50m grid height data. A spatial near dawn temperature pattern over a small area could be explained well by a multiple regression equation of topographic factors for 500m or 1000m square areal units. Height data from the 25m grid showed higher correlation than 50m grid. The effective factors for estimating temperature distribution were the sky view factor, catchment area, height differences from the lowest point and the degree of directional exposure. Distributions of nighttime temperature drops were also examined and could be explained by the same factors. An example of an estimate for minimum air temperature distribution using these factors and data at meteorological observing stations are shown. The percentage of frost damaged buds on tea bushes were also expressed by the topographic factors. Attention should be paid not to extrapolate far from the range of samples because of the statistical basis.