Some examples concerning the meaning of notion "variety" and its role in the increasing of wheat productivity are covered in this article, Some historical aspects of the origin of this term and its use in the select ional work are given. At the example of varieties

The analysis of the structure of State Register of Plant Varieties Suitable for Dissemination in Ukraine is presented. The descriptions of new lupine's varieties important for economic use are given. The state of new varieties introduction in production and ways of improving of the soil fertility with a low humus content and the overcoming of crisis in the forage sphere are shown.

The cost-effectiveness of examination institutions activity of the State System on Plant Variety Protection was developed on the macro level. At the present stage there is an urgent necessity to provide with general methods to solve the tasks of the state scientific-technical program of plant variety examination.

The prospect of rapeseed production in Ukraine Discussed competition of rapeseed oil on the world market, its use for the production of alternative fuels. An assessment of the capacity of rape variety, which is listed in the State Register of plant varieties suitable for distribution in the Ukraine.

The expediency of winter wheat varieties examination in the state variety examination is proved at two levels of agricultural backgrounds: at high level - in the presence of intensive agro technologies and at low level, which is typical for majority of producers. Conclusions have been made under the expediency of improvement and making changes to the Guidelines on evaluation of varieties resistance to diseases and crop tillage with a help of retardants.

Ophiocordyceps sinensis is a famous traditional Chinese medicine adapted to the alpine environment of the Qinghai-Tibet Plateau and adjacent regions. Clarification of the species diversity of Ophiocordyceps sinensis and its relatives could expand the traditional medicinal resources and provide insights into the speciation and adaptation. The study is prompted by the discovery of a new species, O. megala, described here from a biodiversity hotspot in the Hengduan Mountains, China. Combined morphological, ecological, and phylogenetic evidence supports its distinctiveness from O. sinensis, O. xuefengensis, and O. macroacicularis. Additionally, based on the phylogenetic construction of Ophiocordyceps, a special clade was focused phylogenetically on the more closely related O. sinensis complex, which was defined as the O. sinensis- species complex lineage. A total of 10 species were currently confirmed in this lineage. We made a comprehensive comparison of the sexual/asexual morphological structures among this species complex, distinguishing their common and distinctive features. Furthermore, using the method of species distribution modelling, we studied the species ocurrences in relation to climatic, edaphic, and altitudinal variables for the eight species in the O. sinensis-species complex, and determined that their potential distribution could extend from the southeastern Qinghai-Tibet Plateau to the Xuefeng Mountains without isolating barrier. Thus, the biodiversity corridor hypothesis was proposed around the O. sinensis-species complex. Our study highlights the phylogeny, species diversity, and suitable distribution of the O. sinensis-species complex lineage, which should have a positive implication for the resource discovery and adaptive evolution of this unique and valuable group.

Purpose. Identification of spring barley promising breeding lines with combination of adaptive traits under conditions of the central part of the Ukrainian Forest-Steppe.Methods. Field trial, laboratory-field analysis of drought tolerance, statistical and graphical analysis of experimental data.Results. The analysis of variance of the AMMI model showed that the largest contribution to the general variation (85.78%) had environmental conditions (years of research). The value of the genotype was 8.21%, and the genotype by environment interaction was 6.01%. The first and second principal components of both AMMI and GGE biplot explained more than 85% of the genotype-environment interaction. Spring barley breeding lines ‘Deficiens 5162’, ‘Nutans 5073’ and ‘Deficiens 5161’ had the superior combination of yield performance and relative stability through the years according to GGE biplot. With GYT biplot analysis it has been determined that the breeding lines ‘Deficiens 5162’ and ‘Nutans 5073’ also significantly predominated over the other genotypes in terms of combination of yield performance and a number of other traits – 1000 kernels weight, drought tolerance, resistance to pathogens. Breeding lines ‘Deficiens 5161’, ‘Nutans 4966’, ‘Nutans 4705’, ‘Nutans 4816’, ‘Nutans 5184’, ‘Nutans 5193’, which exceeded the mean value in the trial in terms of combination of yield performance and a number of adaptive traits may have practical significance in the breeding process for creation of new initial material.Conclusions. As a result of the complex evaluation when using AMMI, GGE biplot and GYT biplot graphical models the breeding lines ‘Deficiens 5162’ and ‘Nutans 5073’ with the optimal combination of yield, stability, thousand kernel weight and tolerance to abiotic and biotic environmental factors have been identified | Мета. Виділити перспективні селекційні лінії ячменю ярого за комплексом адаптивних ознак в умовах центральної частини Лісостепу України.Методи. Польові випробування, лабораторно-польові дослідження посухостійкості, статис­тичний та графічний аналіз експериментальних даних.Результати. Дисперсійним аналізом AMMI моделі встановлено, що найбільший унесок у загальну варіацію (85,78%) мали умови середовища (років досліджень). Значення генотипу становило 8,21%, а взаємодії генотип–середовище – 6,01%. Перші дві головні компоненти як AMMI, так і GGE biplot, охоплювали понад 85% взаємодії генотип–середовище. Краще поєднання врожайності та відносної стабільності за роками відповідно до GGE biplot мали селекційні лінії ячменю ярого ‘Дефіцієнс 5162’, ‘Нутанс 5073’ і ‘Дефіцієнс 5161’. GYT biplot аналізом визначено, що селекційні лінії ‘Дефіцієнс 5162’ і ‘Нутанс 5073’ також суттєво переважали решту генотипів за поєднанням урожайності та низки інших ознак – маси 1000 зерен, посухостійкості, стійкості проти збудників хвороб. Селекційні лінії ‘Дефіцієнс 5161’, ‘Нутанс 4966’, ‘Нутанс 4705’, ‘Нутанс 4816’, ‘Нутанс 5184’, ‘Нутанс 5193’, які перевищували середнє значення в досліді за поєднанням врожайності та низки адаптивних ознак, можуть мати практичну цінність у селекційному процесі для створення нового вихідного матеріалу.Висновки. У результаті комплексного оцінювання з використанням графічних моделей AMMI, GGE biplot та GYT biplot виділено селекційні лінії ячменю ярого ‘Дефіцієнс 5162’ і ‘Нутанс 5073’ з оптимальним поєднанням урожайності, стабільності, маси 1000 зерен та стійкості до біо- та абіотичних чинників.

Мета. Виділити перспективні селекційні лінії ячменю ярого за комплексом адаптивних ознак в умовах центральної частини Лісостепу України. Методи. Польові випробування, лабораторно-польові дослідження посухостійкості, статис­тичний та графічний аналіз експериментальних даних. Результати. Дисперсійним аналізом AMMI моделі встановлено, що найбільший унесок у загальну варіацію (85,78%) мали умови середовища (років досліджень). Значення генотипу становило 8,21%, а взаємодії генотип–середовище – 6,01%. Перші дві головні компоненти як AMMI, так і GGE biplot, охоплювали понад 85% взаємодії генотип–середовище. Краще поєднання врожайності та відносної стабільності за роками відповідно до GGE biplot мали селекційні лінії ячменю ярого ‘Дефіцієнс 5162’, ‘Нутанс 5073’ і ‘Дефіцієнс 5161’. GYT biplot аналізом визначено, що селекційні лінії ‘Дефіцієнс 5162’ і ‘Нутанс 5073’ також суттєво переважали решту генотипів за поєднанням урожайності та низки інших ознак – маси 1000 зерен, посухостійкості, стійкості проти збудників хвороб. Селекційні лінії ‘Дефіцієнс 5161’, ‘Нутанс 4966’, ‘Нутанс 4705’, ‘Нутанс 4816’, ‘Нутанс 5184’, ‘Нутанс 5193’, які перевищували середнє значення в досліді за поєднанням врожайності та низки адаптивних ознак, можуть мати практичну цінність у селекційному процесі для створення нового вихідного матеріалу. Висновки. У результаті комплексного оцінювання з використанням графічних моделей AMMI, GGE biplot та GYT biplot виділено селекційні лінії ячменю ярого ‘Дефіцієнс 5162’ і ‘Нутанс 5073’ з оптимальним поєднанням урожайності, стабільності, маси 1000 зерен та стійкості до біо- та абіотичних чинників.

Purpose. To reveal the peculiarities of the seasonal rhythm of growth and development of Itoh Group peony cultivars in the conditions of the M. M. Hryshko National Botanical Garden National Academy of Sciences of Ukraine.Methods. The objects of research were plants of 24 cultivars of Itoh Group peonies. The research was conducted on the experimental field of the Department of Flowering and Ornamental Plants of the M. M. Hryshko National Botanical Garden National Academy of Sciences of Ukraine during 2017–2020. The sum of effective temperatures was calculated by summing the daily air temperatures reduced by the biological zero.                 Results. The phenological phases of Ito Group cultivars growth were determined. Phenological spectra for different groups are presented. It was determined that the flowering of early cultivars: ‘First Arrival’, ‘Hillary’, ‘Julia Rose’, ‘Morning Lilac’, ‘Old Rose Dandy’, ‘Sonoma Apricot’ starts at the sum of effective temperatures ≥ 400 °С. The middle group hybrids bloom when the sum of temperatures reaches 450 °С. This group includes: ‘Bartzella’, ‘Callie’s Memory’, ‘Cora Louise’, ‘Lollipop’, ‘Scarlet Heaven’, ‘Sonoma Velvet Ruby’, ‘Yellow Dream’, ‘Yellow Emperor’, ‘Yellow Heaven’, ‘Yellow Waterlily’. Late flowering group includes: ‘Border Charm’, ‘Garden Treasure’, ‘Kopper Kettle’, ‘Pastel Splendor’, ‘Prairie Charm’, ‘Viking Full Moon’, ‘White Emperor’, ‘Yankee Doodle Dandy’; accumulation of effective temperatures above 500 °С is an essential requirement for their flowering.Conclusions. Itoh Group cultivars successfully pass all phases of seasonal development and manage to complete the growing season. Cultivars belong to the spring-summer-autumn-green phenorhythmotype. The onset of the corresponding phenological phases in peonies of the studied group of cultivars requires a certain sum of effective temperatures. Plant outgrowth begins on March 23 – April 2, when the sum of effective temperatures ranges from 20–40 °С. The flowering of varieties characterized as late spring, lasts 6–9 days ± 3–4 days, depending on the varietal characteristics and the year of cultivation. A rapid increase in the sum of effective temperatures up to 700 °C shortens the flowering phase by 4–5 days. An assortment of early (May 22–25 ± 2–3 days), medium (May 26–28 ± 3–5 days) and late-flowering (May 29–31 ± 4–6 days) cultivars has been selected, what ensures the continuity of peony flowering during two months. | Мета. Установити особливості сезонного ритму росту й розвитку сортів півоній Itoh Group в умовах Національного ботанічного саду імені М. М. Гришка НАН України (НБС).Методи. Об’єктом досліджень слугували рослини 24 сортів півоній Itoh Gp. Дослідження проводили на експериментальній ділянці відділу квітниково-декоративних рослин НБС протягом 2017–2020 рр. Суму ефективних температур обраховували через сумування добових температур повітря, зменшених на значення біологічного мінімуму.Результати. Виділено фенологічні фази росту й розвитку рослин півоній Іто-групи. Побудовано фенологічні спектри для різних феногруп. Установлено, що цвітіння ранніх сортів – ‘First Arrival’, ‘Hillary’, ‘Julia Rose’, ‘Morning Lilac’, ‘Old Rose Dandy’, ‘Sonoma Apricot’ – розпочинається за суми ефективних температур ≥ 400 °С. Сорти рослин середньої групи зацвітають, коли сума температур сягає 450 °С. До цієї групи належать ‘Bartzella’, ‘Callie’s Memory’, ‘Cora Louise’, ‘Lollipop’, ‘Scarlet Heaven’, ‘Sonoma Velvet Ruby’, ‘Yellow Dream’, ‘Yellow Emperor’, ‘Yellow Heaven’, ‘Yellow Waterlily’. Пізньоквітуюча група включає сорти ‘Border Charm’, ‘Garden Treasure’, ‘Kopper Kettle’, ‘Pastel Splendor’, ‘Prairie Charm’, ‘Viking Full Moon’, ‘White Emperor’, ‘Yankee Doodle Dandy’, необхідною умовою цвітіння яких є накопичення ефективних температур понад 500 °С.Висновки. Рослини сортів півоній Itoh Gp успішно проходять усі фази сезонного розвитку та встигають завершити вегетацію. За тривалістю вегетації вони належать до весняно-літньо-осінньозеленого феноритмотипу. Настання відповідних фенологічних фаз у півоній досліджуваної групи сортів потребує певної суми ефективних температур. Відростання сортів розпочинається 23 березня – 2 квітня, коли сума ефективних температур змінюється в межах 20–40 °С. Цвітіння сортів характеризується як пізньовесняне, триває 9–16 діб ± 3–4 доби й залежить від сортових особливостей рослин та року вирощування. Швидке наростання суми ефективних температур до 700 °C під час цвітіння рослин скорочує його тривалість на 4–5 діб. Аналіз фенологічних спектрів сезонного розвитку рослин дав змогу виділити сортимент ранньо‑ (22–25 травня ± 2–3 доби), середньо‑ (26–28 травня ± 3–5 діб) та пізньоквітуючих (29–31 травня ± 4–6 діб) півоній Itoh Gp, що забезпечує безперервність їхнього цвітіння загалом упродовж двох місяців.

Purpose. To reveal the peculiarities of the seasonal rhythm of growth and development of Itoh Group peony cultivars in the conditions of the M. M. Hryshko National Botanical Garden National Academy of Sciences of Ukraine. Methods. The objects of research were plants of 24 cultivars of Itoh Group peonies. The research was conducted on the experimental field of the Department of Flowering and Ornamental Plants of the M. M. Hryshko National Botanical Garden National Academy of Sciences of Ukraine during 2017–2020. The sum of effective temperatures was calculated by summing the daily air temperatures reduced by the biological zero. Results. The phenological phases of Ito Group cultivars growth were determined. Phenological spectra for different groups are presented. It was determined that the flowering of early cultivars: ‘First Arrival’, ‘Hillary’, ‘Julia Rose’, ‘Morning Lilac’, ‘Old Rose Dandy’, ‘Sonoma Apricot’ starts at the sum of effective temperatures ≥ 400 °С. The middle group hybrids bloom when the sum of temperatures reaches 450 °С. This group includes: ‘Bartzella’, ‘Callie’s Memory’, ‘Cora Louise’, ‘Lollipop’, ‘Scarlet Heaven’, ‘Sonoma Velvet Ruby’, ‘Yellow Dream’, ‘Yellow Emperor’, ‘Yellow Heaven’, ‘Yellow Waterlily’. Late flowering group includes: ‘Border Charm’, ‘Garden Treasure’, ‘Kopper Kettle’, ‘Pastel Splendor’, ‘Prairie Charm’, ‘Viking Full Moon’, ‘White Emperor’, ‘Yankee Doodle Dandy’; accumulation of effective temperatures above 500 °С is an essential requirement for their flowering. Conclusions. Itoh Group cultivars successfully pass all phases of seasonal development and manage to complete the growing season. Cultivars belong to the spring-summer-autumn-green phenorhythmotype. The onset of the corresponding phenological phases in peonies of the studied group of cultivars requires a certain sum of effective temperatures. Plant outgrowth begins on March 23 – April 2, when the sum of effective temperatures ranges from 20–40 °С. The flowering of varieties characterized as late spring, lasts 6–9 days ± 3–4 days, depending on the varietal characteristics and the year of cultivation. A rapid increase in the sum of effective temperatures up to 700 °C shortens the flowering phase by 4–5 days. An assortment of early (May 22–25 ± 2–3 days), medium (May 26–28 ± 3–5 days) and late-flowering (May 29–31 ± 4–6 days) cultivars has been selected, what ensures the continuity of peony flowering during two months.

Purpose. To reveal the peculiarities of the seasonal rhythm of growth and development of Itoh Group peony cultivars in the conditions of the M. M. Hryshko National Botanical Garden National Academy of Sciences of Ukraine. Methods. The objects of research were plants of 24 cultivars of Itoh Group peonies. The research was conducted on the experimental field of the Department of Flowering and Ornamental Plants of the M. M. Hryshko National Botanical Garden National Academy of Sciences of Ukraine during 2017–2020. The sum of effective temperatures was calculated by summing the daily air temperatures reduced by the biological zero.                 Results. The phenological phases of Ito Group cultivars growth were determined. Phenological spectra for different groups are presented. It was determined that the flowering of early cultivars: ‘First Arrival’, ‘Hillary’, ‘Julia Rose’, ‘Morning Lilac’, ‘Old Rose Dandy’, ‘Sonoma Apricot’ starts at the sum of effective temperatures ≥ 400 °С. The middle group hybrids bloom when the sum of temperatures reaches 450 °С. This group includes: ‘Bartzella’, ‘Callie’s Memory’, ‘Cora Louise’, ‘Lollipop’, ‘Scarlet Heaven’, ‘Sonoma Velvet Ruby’, ‘Yellow Dream’, ‘Yellow Emperor’, ‘Yellow Heaven’, ‘Yellow Waterlily’. Late flowering group includes: ‘Border Charm’, ‘Garden Treasure’, ‘Kopper Kettle’, ‘Pastel Splendor’, ‘Prairie Charm’, ‘Viking Full Moon’, ‘White Emperor’, ‘Yankee Doodle Dandy’; accumulation of effective temperatures above 500 °С is an essential requirement for their flowering. Conclusions. Itoh Group cultivars successfully pass all phases of seasonal development and manage to complete the growing season. Cultivars belong to the spring-summer-autumn-green phenorhythmotype. The onset of the corresponding phenological phases in peonies of the studied group of cultivars requires a certain sum of effective temperatures. Plant outgrowth begins on March 23 – April 2, when the sum of effective temperatures ranges from 20–40 °С. The flowering of varieties characterized as late spring, lasts 6–9 days ± 3–4 days, depending on the varietal characteristics and the year of cultivation. A rapid increase in the sum of effective temperatures up to 700 °C shortens the flowering phase by 4–5 days. An assortment of early (May 22–25 ± 2–3 days), medium (May 26–28 ± 3–5 days) and late-flowering (May 29–31 ± 4–6 days) cultivars has been selected, what ensures the continuity of peony flowering during two months.

Purpose. Jute mallow (Corchorus olitorius L.) is a mucilaginous vegetable and fiber crop cultivated in the tropics, where catnip (Nepeta cataria L.) and Mexican sunflower (Tithonia diversifolia L.) are common weeds. Hence, the study investigated the growth, yield, and nutrient level of jute mallow in weed-free, catnip, and Mexican sunflower environments.Methods. The study involved two screen-house experiments in a Completely Randomized Design (CRD) with six replications. The treatments were 0 (control), 2, 4, 6, 8, and 10 weed plants per pot in both experiments. These are 0, 100, 200, 300, 400, and 500 weed count per square meter equivalent, based on the surface area of the pots used. Mexican sunflower and catnip plants interacted with jute plants in the first and second experiments, respectively. Growth parameters of jute mallow were recorded weekly from 5 to 8 weeks after sowing (WAS), and harvesting was done at 8 WAS. The proximate composition of jute was evaluated using standard procedures outlined by AOAC. The data collected were subjected to analysis of variance (ANOVA), and means were separated using Duncan Multiple Range Test (DMRT) at P < 0.05.Results. Catnip and Mexican sunflower negatively impacted the morphological features of jute mallow from 100 plants per square meter upwards. Catnip and Mexican sunflower, at 300 and 100?500 plants per square meter, respectively, reduced the dry weight of jute mallow. The crude protein content of jute mallow was also lessened by Mexican sunflower at some point.Conclusions. The study recommends that the density of catnip and Mexican sunflower plants interacting with jute mallow should be maintained below 100 plants per square meter to prevent yield loss. | ????. ???? ???????????? (Corchorus olitorius L) ? ?? ??????? ? ??????? ????????, ??? ????????? ? ????????. ?????????? ?????????, ?? ?????????? ???? ??????, ? ?????? ????? ???????? (Nepeta cataria L.) ? ????????????? ???????? (Tithonia diversifolia?L). ? ?????? ??????????? ??????? ????, ??????????? ? ????? ?????? ??????????? ? ???????? ????? ????????????? ?? ????? ??????????? ??????? ????? ?????????? ? ?????????????? ????????? ?? ? ??????????, ???????? ??? ????????.??????. ??????????? ???????? ??? ???????????? ???????????? ?? ???????? ?????????????? ?????? ? ????? ???????????. ????? ??????? ? ????????????? ???? ?????: 0 (????????), 2, 4, 6, 8 ? 10 ???????? ?? ??????? ??? ???????????. ? ??????????? ????? ???????? ???????????? ????????, ???? ????????? ??????????? 0, 100, 200, 300, 400 ? 500 ???????? ?? 1??2. ????????? ????? ????? ????????????? ??????????? ??????? ? 5 ?? 8 ????? ????? ?????, ? ?????? ??????? ????? 8 ??????. ????? ?????? ?????? ? ???????? ????? ????????? ? ????????????? ??????????? ????????, ?????????? ?????????? ????????? ????????????????????? ???????. ???????? ?????????? ???? ????????? ?? ????????????? ??????? ????????????? ??????? (ANOVA).??????????. ?????? ????? ???????? ? ?????????????? ???????? ?? ????????? ??? 100 ?????? ?? ???????????? ???? ??????? ????????? ???????? ?? ???????????? ???????????????? ????? ?????????????. ?? ???????, ?? ??????????? 100?500 ?????? ?? ?????????? ????, ??????????? ????? ????????? ????? ???? ????? ?????????????. ?? ????????????, ????????????? ???????? ???? ????? ??????????? ????????? ?????? ?????? ???????? ? ????? ?????????????.????????. ??? ??????????? ????? ?????? ?????????????? ???????????? ??????????? ?????? ??????? ????? ??????????? ?? ?????????????? ????????? ? ??????? ????? ??????????????? ?????? ??? 100 ??./?2.

Purpose. Jute mallow (Corchorus olitorius L.) is a mucilaginous vegetable and fiber crop cultivated in the tropics, where catnip (Nepeta cataria L.) and Mexican sunflower (Tithonia diversifolia L.) are common weeds. Hence, the study investigated the growth, yield, and nutrient level of jute mallow in weed-free, catnip, and Mexican sunflower environments. Methods. The study involved two screen-house experiments in a Completely Randomized Design (CRD) with six replications. The treatments were 0 (control), 2, 4, 6, 8, and 10 weed plants per pot in both experiments. These are 0, 100, 200, 300, 400, and 500 weed count per square meter equivalent, based on the surface area of the pots used. Mexican sunflower and catnip plants interacted with jute plants in the first and second experiments, respectively. Growth parameters of jute mallow were recorded weekly from 5 to 8 weeks after sowing (WAS), and harvesting was done at 8 WAS. The proximate composition of jute was evaluated using standard procedures outlined by AOAC. The data collected were subjected to analysis of variance (ANOVA), and means were separated using Duncan Multiple Range Test (DMRT) at P < 0.05. Results. Catnip and Mexican sunflower negatively impacted the morphological features of jute mallow from 100 plants per square meter upwards. Catnip and Mexican sunflower, at 300 and 100–500 plants per square meter, respectively, reduced the dry weight of jute mallow. The crude protein content of jute mallow was also lessened by Mexican sunflower at some point. Conclusions. The study recommends that the density of catnip and Mexican sunflower plants interacting with jute mallow should be maintained below 100 plants per square meter to prevent yield loss.

Purpose. Jute mallow (Corchorus olitorius L.) is a mucilaginous vegetable and fiber crop cultivated in the tropics, where catnip (Nepeta cataria L.) and Mexican sunflower (Tithonia diversifolia L.) are common weeds. Hence, the study investigated the growth, yield, and nutrient level of jute mallow in weed-free, catnip, and Mexican sunflower environments. Methods. The study involved two screen-house experiments in a Completely Randomized Design (CRD) with six replications. The treatments were 0 (control), 2, 4, 6, 8, and 10 weed plants per pot in both experiments. These are 0, 100, 200, 300, 400, and 500 weed count per square meter equivalent, based on the surface area of the pots used. Mexican sunflower and catnip plants interacted with jute plants in the first and second experiments, respectively. Growth parameters of jute mallow were recorded weekly from 5 to 8 weeks after sowing (WAS), and harvesting was done at 8 WAS. The proximate composition of jute was evaluated using standard procedures outlined by AOAC. The data collected were subjected to analysis of variance (ANOVA), and means were separated using Duncan Multiple Range Test (DMRT) at P < 0.05. Results. Catnip and Mexican sunflower negatively impacted the morphological features of jute mallow from 100 plants per square meter upwards. Catnip and Mexican sunflower, at 300 and 100–500 plants per square meter, respectively, reduced the dry weight of jute mallow. The crude protein content of jute mallow was also lessened by Mexican sunflower at some point. Conclusions. The study recommends that the density of catnip and Mexican sunflower plants interacting with jute mallow should be maintained below 100 plants per square meter to prevent yield loss.