PLANT ECOPHYSIOLOGY (ARSANJAN BRANCH)
Year:2018 | Volume:10 | Issue:32 |Papers Count:23

In order to investigate the response of cereals to intercropping with legume in weed competition conditions, a field experiment was performed in 2014-2015 in the College of Agriculture and Natural Resources of Darab, Shiraz University. Treatments included 10 monoculture (wheat, barley, triticale, pea and bean with and without weeds) and 6 intercropping (wheat + chickpea, wheat + faba bean, barley + chickpea, barley + faba bean, triticale + chickpea and triticale + faba bean with Weeds) which laid out in a randomized complete block design (RCBD) with three replications. Results showed that grain yield, biological yield and harvest index in some of intercropping treatments was similar to those in weedy monoculture and even in some cases similar to those in weed-free monoculture treatments which it shows that intercropping had a higher efficiency. For instance, grain yield in barley+ chickpea intercropping (6241 kg ha-1, 15 % reduction compared to weedy monoculture) was not significantly different from weedy barley monoculture (7313 kg ha-1) and weed-free barley monoculture (7621 kg h-1). Partial LER of cereals, in intercropping treatments except wheat+faba bean (0. 39) based on weedy monocultures, was greater than 0. 5 and also except intercropping of triticale + chickpea (0. 31) and wheat + faba bean (0. 41) based on weed-free monocultures was more than 0. 5. Barley had a greatest grain and biological yield over all the treatments which it was because of its superior competitive ability against weeds. Since an intercropped cereals was planted in a less space as monoculture, these results showed that cereals-legume intercropping, especially barley-chickpea or barley-faba bean was more efficient to produce greater yield per unit area.

This experiment was conducted as factorial base on randomized complete blocks design with three replications at Agriculture and Natural Resources Research Station, Samian, Ardabil in 2015. The first factor included three canola cultivars (Hyola 308, Hyola 401 and R. G. S 003), second factor was three row distances (20, 30 and 40 cm) and the third factor comprised of plant distances on row (5 and 10 cm). Results showed that the effect of cultivar was significant on traits of growth and reproductive periods, total growth period, and the number of pods per plant. Effect of cultivar and row spacing interaction was significant on seed oil, thousand seeds weight and seed yield. Also, interaction between cultivar, row spacing, and plant distances was significant on all traits except for oil yield. Spring rapeseed, Hyola 308 cultivar showed the highest seed yield (2. 55 t ha-1), the highest pod per plant (338. 89), and seed per plant (9536) in combination treatment of 20 cm row spacing and plant distance of 5 cm. Also, the highest oil yield (899. 05 kg ha-1) was achieved by Hyola 308 planted in 20 and 30 cm row spacing. Having total period of vegetative and reproductive growth of 103 days, Hyola 308 cultivar was determined as the earliest growing cultivar. Generally, results showed that the Hyola 308, as early growing and high yielding cultivar, gained the highest oil and seed yield in combination treatment of plant spacing of 5 × 20 cm for this region.

In order to evaluate of sowing Date, row spacing and Zinc and nitrogen ferttilizers on yield Components and yield of chichpea(var. Arman), an Experiment was carried out at the Agricultural research station of Gonbad for two years(2010-2012). The expermiant was factorial arranged With two sowing dat(Nov 6-dec6 and dec26), two row spacing(24 and36 centimeters), two zinc Levels(0 and 30 kg/ha) and two nitrogen foliar application (without and spraying urea 1%) in a Randomized compeat block design with three replication. Plots consisted of fout meter-long rows spaced 24, 36 cm apart. Fertilizer was applied separately for every plots on the base of soil test. But zinc sulphate was only to add plots containing Zinc treatment seed per pod, . Traits such as pod number, seed number in measured. The results revealed that effects of zinc sulphate on seed yield and foliar application of nitrogen on number of pod and plant height were significant.

This experiment was carried out to investigate effects of foliar application of selenium and different Urea top-dressing methods on agronomic and physiological characteristics of rain fed wheat sardari cultivar during the growing season 2012-2013. Experimental factors were four levels of different Urea top-dressing methods (without application of Urea top-dressing; application of 60 kg/ha in tillering stage; application of 30 kg/ha in tillering stage combined with 200 mg/Lit before spike emergence; application of 20 kg/ha in tillering stage combined with 200 mg/Lit before spike emergence and 200 mg/Lit in the last spike emergence stage) and three levels of selenium (0, 5 and 10 mg/Lit). The results showed that the foliar application of selenium at 5 and 10 mg/lit decreased cell ion leakage by 6. 7% and 5. 3% compared to control, respectively. The application of 20 kg Urea/ha in the tillering stage combined with twice foliar application in reproductive stage at 200 mg/Lit along with foliar application of 10 mg/Lit selenium increased grain yield by 44. 3% compared to the control and 12% compared to treatment of application 60 kg Urea/ha in the tillering stage. It could be concluded that by applying of 30 kg Urea/ha in the tillering stage combined with once foliar application in reproductive stage can be decreased by 50% Urea fertilizer application and obtain optimum yield.

Regarding to demands of country edible oil as well as increasing deficiency of water for agriculture, understanding and evaluating the sunflower growth and yield traits, especially in relation to drought stress can have important effect on yield increase. To evaluate sunflower inbred lines under optimum and water stress conditions, two separate experiments was conducted at Agricultural Research Station of Bastam (Shahrood). In each experiment, 20 French inbred lines in a randomized complete blocks design with three replications were evaluated. Irrigation of optimum and stress experiment was 100% and 50% of water requirement based on FAO-Penman– Monteith equation, respectively. During the growing period, agronomic traits including the number of days to flowering, maturity, plant height, stem diameter, head diameter, number of grains per head, biomass, grain yield and 1000 grain weight were measured. Due to the precise measurement of the amount of water in both experiments, water productivity was calculated by ratio of grain yield to used water. According to the results, there was a significant difference between lines in all traits. Lines C111, C138, C142 and C148 had the highest grain yield and water productivity in both moisture conditions. Line C123 showed maximum grain yield reduction (87%), with 1736 and 224 kgha-1 grain yield under optimum and water stress conditions, respectively. In contrast, line C122 showed minimum grain yield reduction (35%), with 1493 and 978 kgha-1 grain yield under optimum and water stress conditions, respectively. In the path analysis of traits, two traits, grain number per head and 1000 grain weight showed most direct effect on grain yield in both conditions. Due to high heritability of these two traits, we can use them in selection for grain yield increase.

Since stomatal conductance (gs) couples the crop photosynthesis and transpiration, estimation of gs is important for adopting management practices which can increase crop growth through efficient use of water. In the current study, a simple model based on temperature difference between crop leaf and a reference surface was used for estimation of the leaf stomatal conductance. The model calibrated and validated using two years field experiment data with pumpkin carried out during 2013 and 2014 at Research Farm of Ferdowsi University of Mashhad. Results showed that model had a very good performance and very accurately simulated pumpkin leaf stomatal conductance under conditions without nitrogen deficiency. Under nitrogen deficient conditions, by using the nitrogen nutrition index (NNI), the good or very good performance and accuracy were obtained from the model. The relative difference (RD) between simulated and observed values of average of stomatal conductance during the growing season was ranged from 1. 1% to 2. 5 for non-nitrogen deficient treatments and from 2. 8% to 5% for nitrogen deficient treatments. The accuracy and simplicity of the model and its low input requirements make it suitable for use in stomatal conductance based crop growth models.

In order to evaluate the effect of salycilic acid on some reproductive and yield of safflower under drought stress an experiment was conducted in 2015 at research farm of Islamic Azad University of Tabriz in form of split plot based on randomized complete block design with three replications. The main factor included water stress (S) at two levels of evaporation (70 and 140 mm) from the surface of Class A basin. Post-establishment irrigation (the 4 leaves stage) was applied until the physiological maturity figures were obtained. The first sub-factor included salicylic acid in 3 control levels (distilled water spraying), spraying with concentrations of 100 and 200 mg per liter. The second sub-factor included local safflower of Isfahan and the Isfahan (Goldasht) cultivars. The results showed that water stress causes a significant reduction in plant height, number of sub branches, the number of heads per plant, number of seeds per head, seed weight, number of seeds per plant and yield. Salycilic acid effect on growth and yield under non-stress was felt that the use of different concentrations of salycilic acid significantly increased the number of branches, number of heads per plant, number of seeds per plant and seed yield in the absence of stress and the highest increase in 100 mg per liter salycilic acid was obtained. Spying had no significant effect on grain yield in drought stress conditions and in these conditions only plant height and number of branches increased. In general, the results showed that although in drought conditions negative effect on grain yield with consuming salycilic acid decreased, but the use of small amounts (concentration of 100 mg/ l) can be somewhat alleviated the negative effects of stress on plant growth. Type cultivars significantly influenced traits and results of mean comparison showed that Goldasht had highest plant height, number of lateral branches, number of heads per plant, number of seeds per head, number of seeds per plant and yield. As for interactions, the interaction between water stress and variety on number of branches, numbers of seeds per plant and seed yield were significant. The highest number of brances, number of seed in plant and seed yield obtained from 70 mm irrigation and glodasht. Therefore, this variety had better and more effective defence system than the local variety and was tolrerance to rought stress.

In current research, the forage yield and quality of 49 accessions of alfalfa (Medicago sativa) were examined using simple lattice design with 2 replications under dryland farming system during 2005-2007 in the Agriculture Research Station of Khosroshahr-Eastern Azerbaijan. The traits: forage dry matter yield, plant height, growth vigour, flowering date, leaf to stem ratio and quality traits consisted of dry matter digestibility, crude protein, water soluble carbohydrates, crude fiber, acid detergent fiber, neutral detergent fiber and total ash were evaluated during 2 years (2006-2007). The results of combined analysis showed significant differences among accessions and among years. Total means of forage dry matter yield were 5. 43, 4. 45 t/ha in years 2 and 3, respectively. The results of correlation analysis among traits indicated that selection for higher forage dry matter yield was produced with earlier flowering, tall plant height and major growth vigour. Considering to negative relationship of forage dry matter yield and quality, from between genotypes with high yield, mostly were selected high the amount of leaf to stem ratio, crude protein, dry matter digestibility, water soluble carbohydrates, and total ash and down amount of crude fiber, acid detergent fiber and neutral detergent fiber. For this purpose the genotypes of Khoramabad, Ghara yonja, Flavarjan, Ghazaghestan and Kordestan with average values of 6. 5 – 8. 5 t/ha forage dry matter yield were tendered for produced synthetic variety.

A field study carried out during 2014-2015 to investigate the effect of various plant hormones, applied single or in combination, on grain yield, yield components and protein content of barley cultivar of Sararood under dryland farming. Experiment conducted at farm research of Ilam university a randomized complete block design consisted of 8 treatments including control, IAA, GA, KIN, IAA+GA, IAA+KIN, GA+KIN and IAA+KIN+GA, replicated in three times. Foliar application of hormones was done when plants were at flowering stage. Results showed that foliar application of hormone treatments resulted in enhanced total chlorophyll, chlorophyll a contents, 1000-grain weight and grain protein content. Foliar application combination of IAA+ KIN had the greatest promoting effects on total chlorophyll and chlorophyll a contents, 1000-grain weight and grain protein and increased total chlorophyll, chlorophyll a contents, 1000-grain weight and grain protein content by 8. 69, 10. 6 and 9. 85%, respectively. Foliar application of hormones, single or in combination, had not significantly effect on plant height, total number of spike m-2, grain number spike-1, grain yield and harvest index. Overall, results of this experiment suggested partial positive effect of plant hormone on agronomic traits of barley under dry land farming.

According existence of huge reserves of water and saline soil in Iran, use of halophyte plants is inevitable as new source of sustainable production of forage, protein and oil for meet nutritional needs of the growing population of the country. In this study, Iranian salinity researches on halophytes from 1977 right now were investigated and analyzed, the challenges were discussed and finally some approaches were provided for future. Based on definition in this study, “ halophytes are the plants adapted to saline conditions via one of the mechanisms of prevent salt entry to plant or reduced salt concentration in cytoplasm” . Therefore, the halophytes can be divided in two major classes: eu-halophytes and facultative halophytes. Literature review of the country revealed that considerable researches in halophytes has begun from the last half century and were remarkably increased from 2001 right now. The plants such as kochia (Kochia scoparia), purslane (Portulaca oleracea) and lambsquarter (Chenopodium album) have been well evaluated in terms of different growing aspects and it seems that some other plants such as quinoa (Chenopodium quinoa) and salicornia (Salicornia spp. ) have greater potential for attracting the researches. About 30%, 11%, 11%, 11%, 9%, 7% and 28% of these researches were conducted on growth aspects, physiological and biochemical traits, forage quality, implementation of strategies to improve production, plant nutrient and fertilization, oil status and others, respectively. The experiments in controlled conditions were more than twice as field experiments. In general, regard to more investigation on forage and oil quality of halophytes, the aspects of medical, sanitary and ornamental of halophytes should be evaluated in sustainable agriculture systems.

Crop simulation models are useful tools for determination of optimum strategies for crop management and sustainability of the agricultural ecosystems. The aim of this study was to evaluate the effect of different sowing dates on grain yield, biological yield and water use efficiency of chickpea (Bivanij cultivar) under rainfed conditions at five locations in Kermanshah province. For this purpose, the SSMChickpea model with historical daily weather data for the period of 1985– 2014, were used. The results showed that early sowing date increased leaf area and biological yield and eliminated terminal drought stress. The highest and lowest grain yield was obtained on 20 February and 4 March sowing dates with 1269 and 446 kg ha-1, respectively. The delayed sowing date substantially reduced grain yield by 64%. Furthermore, the highest and lowest biological yield was obtained on 20 February (3448 kg ha-1) and 21April (2217 kg ha-1). On the other hand, the greatest water use efficiency was obtained on 20 February (6. 6 kg ha-1 mm-1). Therefore, in Kermanshah province with a cold semi-arid and arid climate, the farmers with early sowing (20 February) could improve water use efficiency, biological yield and average productivity of rainfed chickpea because earlier sowing dates resulted in the longer growing season, more concurrency rainfall with growing season. It also concluded that early-sowing crops flowered and matured earlier and escaped later drought.

In order to study the effects of biological nutrition and irrigation managements on qualitative indices of fenugreek, an experiment was carried out in split plot based on a Randomized Complete Block Design with three replications and 15 treatments at Research Station, Faculty of Agriculture, Azad University, Birjand, Iran, during growing season of 2010-2011. Experimental treatments included irrigation interval (in three levels including irrigation every 6, 9 and 12 days) and biofertilizer (in five levels including nitroxin, biosphere, and micorhyza fungi of G. mosseae, G. intraradices and control treatment or none fertilizer). Results of statistical analysis showed that irrigation treatments had a significant effect on physiological indices like carbohydrate, chlorophyll a, ash, Na, K and proline. The effect of biofertilizer was significant on carbohydrate, chlorophyll a, and on ash. Results showed that proline, carbohydrate, Na, chlorophyll b and ash improved by increasing irrigation interval to every 12 days but K and chlorophyll a decreased. The highest content of carbohydrate, chlorophyll and ashwere observed in G. mosseae, biosphere and G. intraradices, respectively. Overall, results showed that application of biofertilizers had positive effects on qualitative indices of fenugreek and created type of plant adaptation to drought stress.

In this decade, plants with low requirements which may contribute to human health have been increasingly considered. To investigate the effect of irrigation interval and foliar application of micronutrients on Panicum miliaceum, an experiment was conducted as split plot arrangement based on randomized complete block design with three replications in Sarbisheh agricultural research farm in 2012. Treatments including irrigation interval (7, 14 and 21 days) and foliar application of micronutrients in four levels (foliar application of manganese, zinc, zinc manganese and without foliar application) were assigned to main plot and sub plot, respectively. By decreasing irrigation interval to 7 days, the grain yield was increased mainly through increasing the number of grains per panicle (28% towards 21 day irrigation interval) and increasing the number of panicles per plant (25. 68% towards 21 day irrigation interval). The foliar application of micronutrients improved the grain yield through enhancing grain number per panicle (23. 29% towards treatment without foliar application) and enhancing panicle number per plant (15. 17% towards treatment without foliar application). Findings showed that decreasing irrigation interval to 7 days and foliar application of micronutrients increased the yield and yield components of Panicum miliaceum. The maximum grain yield (222. 6 g per square meter) was under 7 day irrigation conditions and foliar application of manganese and zinc.

Safflower (Carthamus tinctorius) is one of the most important agronomic and medicinal crops in Iran, that it’ s potential yield and limitations can be determined using a simple model and long-term meteorological data. This study was performed to yield prediction and statistical modeling of Safflower based on meteorological indicators and climatic parameters. Phenology, dry matter production and distribution and soil-water balance sub models should be studied in order to growth stages and yield prediction in agricultural crops. Parameters related to each sub model were estimated using data reported on different sowing dates during the years 2002-2015 in Isfahan region and the data reported by other researchers in other regions. Growth and yield changes were calculated by phenology, dry matter production and distribution using meteorological data (minimum and maximum temperatures, radiation and rainfall) from Isfahan region, and the safflower crop yield at the end of growing season was predicted. One of the model evaluation criteria is comparison of coefficient of linear regression between observed and predicted yield (a= 0. 46 ± 0. 073, b= 1. 49 ± 0. 18) with coefficient of line 1: 1. In the field experiments the limit for Coefficient of variation (CV) is 20 to 25. Accuracy of the model was high, regarding to the coefficient of variation of predicted and observed grain yield (CV=8. 89). R2 of grain yield was 0. 75, which is indicating that predicted data are 70 percent likely match with observed data. Variation range for observed data was 1. 2 to 4. 61 tones per hectar and the mean was 2. 9 tones and for the predicted data it was 1. 94 to 3. 62 tones per hectar and the mean was 2. 78 Tones per hectar. In all cases, simulated yield compliance with observed yield. Hence, given the ability of the model to simulate the phonological stages of safflower, it can be used as a suitable tool for planning and better management of safflower fields in Isfahan.

In order to investigate the effect of integrated weed management on some growth and quality traits of cowpea, an experiment was conducted at the research field of Shahrood University of Technology as randomized complete blocks design with four replications in 2014. The experiment consisted of 12 treatments; weedy, weed free (all season), recommended herbicide dose (960 grams active ingredient per hectare), reduced herbicide dose (480 grams active ingredient per hectare), ultrasonic waves (24 kHz for 6 minutes) and hydro-priming separately in combination with the above mentioned treatments. The results showed that leaf area index and height of the first pod insertion increased in ultrasonic waves + weeding (all season) treatment by 51. 6 and 60 percent in comparison to control (no weeding) treatment respectively. Ultrasonic waves + weeding and hydro-priming + weeding treatments increased the grain protein by 7. 3 and 7. 5 percent in comparison to control (no weeding) treatment respectively. The results indicated that application of hydro-priming and ultrasonic waves in combination with redused dose of trifluralin increased the leaf chlorophyll index and grain yield equal to recommended herbicide dose and weeding (all season) treatments. Also no significant difference was observed in density and above ground biomass of weeds between the application of hydro-priming + reduced herbicide dose and ultrasonic waves + reduced herbicide dose treatments with recommended herbicide dose treatment. Based on the results of this experiment, priming and sonication of seeds in combination with reduced dose of herbicide can increase growth and quality traits and also reduce herbicide consumption.

This study was done to investigate the effects of urea and phosphate on madder in saline conditions at Research Farm of Isfahan Agricultural and Natural Resources Research Center located in the Rodasht city. A factorial experiment based on randomized complete block design with three replications was designed. Treatments consist of urea with 4 levels of zero, 50, 100 and 150 kg/ha and Triple Super Phosphate fertilizer with 4 levels of zero, 50, 100 and 150 kg/ha. Vegetative growth characteristics such as plant height, leaf dry weight, leaf area, panicle length and weight of 1000 fruits, biomass and root yield were measured. Analysis of variance in the third year, showed the effects of nitrogen and phosphorus fertilizer on plant growth characteristics of madder else the leaf area, panicle length and 1000 fruits weight was statistically significant. The highest yield of shoots was obtained due to application of 150 kg/ha urea and 150 kg/ha triple super phosphate as much as 1. 74 kg/m2. The highest yield of roots was obtained due to application of 100 kg/ha urea and 100 kg/ ha triple super phosphate as much as 0. 34 kg/m2. Totally, for obtaining the highest yield of madder in saline condition, we suggest the application of 150 kg/ha of urea and triple super phosphate.

In order to study the effect of nourishment with chemical bio-fertilizer and manure fertilizers on agrophysiologic characteristics and weed density of maize, an experiment was conducted a split plot based on a randomized complete block design with three replications at Agricultural Research Field Station of Mehran during 2014-2015 cropping season. Nitrogen chemical fertilizer (0, 25, 50, 75 and 100% recommended) was assigned as a main plots and Nitroxin bio-fertilizer (Azospirillum brasilense and Azotobacter chroococcum), manure fertilizer (20ton/ha), co-application of manure and bio-fertilizer and check (without application of biological fertilizer and manure) treatment were arranged as a sub plots. Number of grain per row, number of grain per ear, ear length, plant height, a chlorophyll, b chlorophyll, relative water content, weed density and weed dry weed were significantly affected by main effects of nitrogen and co-application of bio-fertilizer and manure. n this study, interaction effct of nitrogen and coapplication of bio-fertilizer and manure had effect on row er ear, 1000-grain weight, grain yield, biological yield and harvest index. The highest row per ear (20. 6 ear), 1000-grain weight (237. 3 g), grain yield (11900 kg/ha), biological yield (24690 kg/ha) and harvest index (48. 4%) observed in 75 and 100% of nitrogen chemical fertilizer and o-application of bio-fertilizer and manure.

Lawns and ground covers are considered as main source of beautifulness and filtering air atmosphere form dust and toxins, protecting environment from dryness and warmness. Moreover they are major elements in freshness of the atmosphere and reducing environmental pollution. With above idea, current researches have been taken place to investigate cultivation of some endemic lawns and ground covers as replacement for exotic introducing varieties. From a 20 early introduced endemic species, 10 were selected for pot growing alongside with a well known species from Netherland. A factorial static based on a completely randomized design were used for statistical analysis. Major comparing indexes including growth length, greenery during two hot and cold picks, and plant density. Experiment was conducted in 25cm diameter pot, each containing 10 plants and there were four replications for each species. Results showed that four endemic species are comparable with exotic importing species including Ophiopogon sp, Dichondra sp, Cynodon dactylon and Potentilla reptans. The worsen species including Cyperus rotundus, Sphagnum sp, Poa sp and Marchantia polymorpha. Oxalis sp was categorized as middle group.

Haloxylon sp. and Atriplex sp. are among aridity and salt tolerant species which have been planted extensively in practices of combat desertification and arid and semi-arid rangelands reclamation, in recent decades. This study was performed in order to assessment of saxaul and saltbush planting on soil properties in a part of desert rangelands of Mallard Zarandiyeh. Three sites included: control (natural rangeland), Atriplex canescens plantation and Haloxylon persicum plantation types with an area of five hectares for each of them. In each area, 20 plots along six 500 meters transects were located by randomized-sysematic methods for sampling. Soil samples were collected from two depth (0-30 and 30-60 cm) in control and treatment areas (Atriplex and Haloxylon planting) and Soil samples were physically and chemically analyzed in the laboratory for some variables such as: texture, EC, pH, organic carbon, Caco3, P, CA, Mg, N, K, Cl, Na and HCO3-. Data were analyzed by ANOVA. The results showed that except for acidity and silt (%), there were significant differences between Control area and treated areas (planted sites with Atriplex and Haloxylon) in soil variables. Also, Haloxylon pesicum has been caused the salinization and alkalization and calcification of surface soil, more than Atriplex canesces; but regarding to more adaptation, white saxaul seems to be more suitable plant to reclamation of such arid rangelands, as a native species.

In recent years, Querqus trees especially those which are located in the Lorestan province, in the Central Zagros forests, have faced to the Oak decline phenomenon. Different natural and unnatural factors can make this phenomenon to occur. Quercus brantii, the dominant species of the Lorestan forests, is suffered from this phenomenon and it has been degraded in wide range. Quercus brantii contain different type of secondary compositions. Secondary compositions in the leaves react as a defensive mechanism against stress maker conditions. In present study, to investigate the effect of oak decline on the secondary compositions such as total tannin, insoluble suger, principal soluble suger, condensed tannin and antioxidant of the leaves of Quercus branti, some sample of the leaves from affected trees in the Lorestan forests were gathered. After different tests on the leaves of Quercus brantii, the analysis of the acquired data was conducted using the factorial experiment and independent t-test. The rate of total tannin, insoluble suger, principal soluble suger and condensed tannin in the affected tress in the regions of Miankooh, Maleshaban and Abolvafa had a significant difference with the healthy trees but the rate of antioxidant did not show a significant difference. Moreover, the rate of condensed tannin in the regions of Miankooh and Abolvafa were significantly greater than the other areas. Stressful conditions such as oak decline, cause changes in the amount of secondary compounds in leaves. Studying these changes can help diagnosing and controlling the prevalence of stressful conditions.