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Croatian Baranja region contains soils with highly quality crop production properties, but the knowledge of the effects of reduced tillage systems is lacking. Our investigations were conducted under field conditions at Knezevo site chernozem in four replications. They included four soil tillage systems (CT: conventional tillage, with ploughing up to the 30 cm as a primary tillage; DS: diskharrowing up to the 15 cm; CH: chiselling up to the 30 cm + diskharrowing; NT: no-till seed drilling), both for winter wheat ( Triticum aestivum L. )-soybean ( Glycine max L. ) in crop rotation during three growing seasons (2002–2004). All measured crop properties were strongly affected by different seasons, especially with the season of 2003 with extreme drought. Crop biomass in five growth stages for winter wheat showed that at the beginning DS and CH had stronger growth than CT and NT, but differences vanished toward final stages. Winter wheat grain yield achieved by reduced tillage systems was in average either higher (CH=5.59 t ha ⁻¹ ) or not different (5.38 and 5.23 t ha ⁻¹ for DS and NT, respectively) than CT (5.28 t ha ⁻¹ ). Soybean growth was consistently the most impaired at NT system, especially at the full maturity stage, where also DS and CH had lower biomass than CT. Soybean grain yield confirmed biomass results, since NT (2.11 t ha ⁻¹ ) had always the lowest yield, when compared with other tillage systems (CT=2.88, CH=2.77 and DS=2.72 t ha ⁻¹ ). Our conclusion is that within the Croatian Baranja environmental conditions is possible to replace soil tillage based on the ploughing for winter wheat and soybean with reduced soil tillage systems based on disking and chiselling, whereas no-till system still needs solution which will address drought-related problems.

The replenishment of phosphorus (P) in the soil solution is of considerable importance from the standpoint of plant nutrition, since the quantity of inorganic P in the solution phase at any time, is usually insufficient to meet the crops’ requirements during the whole growing season. Acidification is a natural process in the environment; however, human activity often increases this tendency. Through this study we are concerned in the P recovery from soil solid phase that have received different levels of P-additions and of acidification applying three different water extraction methods.A calcareous loamy soil, pH _H2O =7.9 was incubated with 0, 80 and 320 mgPkg ⁻¹ soil for one month. Four different levels of P-acidification (pH 7.9, 7.3, 6.0 and 4.5) were adjusted by adding calculated volumes of HCl and incubating the soil samples for further one month, then equilibrated with different rates of phosphorus as 0, 80, 160 and 240 μgP10cm ⁻³ . The desorbed quantity of phosphorus was determined applying EUF, HWP and multistep desorption methods.Some part of the added phosphorus can be recovered by all methods, depending on the dose and time of P addition (previous or recent), on acidity of the soil and on the method used. The desorbable phosphorus amounts are in average 19 % of sum of P-loading at 0 mgPkg ⁻¹ level, and 31 and 64 % at 80 and 320 mgPkg ⁻¹ levels, respectively. Phosphorus recovery is generally more in acidified soil then in non acidified one but at high fertilizer dose it is somewhat less.

Abstract

If we want to increase the efficiency of precision technologies to create sustainable agriculture, we need to put developments and their application on a new footing; moreover, a general paradigm shift is needed. There is a need to rethink close-at-hand and far-off innovation concepts to further develop precision agriculture, from both an agricultural, landscape, and natural ecosystem sustainability perspective. With this, unnecessary or misdirected developments and innovation chains can be largely avoided. The efficiency of the agrotechnology and the accuracy of yield prediction can be ensured by continuously re-planning during the growing season according to changing conditions (e.g., meteorological) and growing dataset. The aim of the paper is to develop a comprehensive, thought-provoking picture of the potential application of new technologies that can be used in agriculture, primarily in precision technology-based arable field crop production, which emphasizes the importance of continuous analysis and optimisation between the production unit and its environment. It should also be noted that the new system contributes to reconciling agricultural productivity and environmental integrity. The study also presents research results that in many respects bring fundamental changes in technical and technological development in field production. The authors believe that treating the subsystems of agriculture, landscape, and natural ecosystem (ALNE) as an integrated unit will create a new academic interdisciplinarity. ICT, emphasizing WSN (Wireless Sensor Network), remote sensing, cloud computing, AI (Artificial Intelligence), economics, sociology, ethics, and the cooperation with young students in education can play a significant role in research. This study treats these disciplines according to sustainability criteria. The goal is to help management fulfil the most important expectation of reducing the vulnerability of the natural ecosystem. The authors believe that this article may be one of the starting points for a new interdisciplinarity, ALNE.

Fresh water is considered one of the most important factors in expanding the cultivated area. In arid and semi-arid zones, water resources are scarce. Recently many scientists in different countries have concluded that the re-use of wastewater could help to solve water scarcity problems. An additional target is to protect the environment by reducing the pollution load with little or no risk to the plants, groundwater or human health. Therefore, the principal objective of the present study was to demonstrate the economic aspects of re-using secondary treated wastewater in irrigation, in order to make the best use of existing resources. Thus, field trials were established in a rotation of summer and winter crops during the 2000–2002 seasons to evaluate the effect of irrigation with secondary treated wastewater on the yield and quality of field crops compared with canal water. The present study discusses a part of this study, concerning the effect on the yield and quality of lentils and pearl millet. The experimental treatments for both crops were the same in both growing seasons, involving two water irrigation sources (secondary treated wastewater and canal water) and two fertilization treatments (application of recommended rates of chemical fertilizers and control without fertilizer application). The data demonstrated that crops irrigated with secondary treated wastewater performed equally well or significantly better than those irrigated with canal water. Heavy metal concentrations were very low, and had no influence on crop quality, determined as the chemical composition of lentil seeds and the dry forage yield of millet. Animal performance was also taken into consideration. The results indicated that the seed and biological yields of plants given wastewater in the absence of chemical fertilizers were nearly equal to those of plants given the recommended dose of chemical fertilizers, indicating that wastewater could provide an adequate amount of N, P and K to cover crop requirements at different growth stages.

The aim of this study was to evaluate the influence of atmospheric precipitation on the yield of spring malting barley. The plant height and heading of the studied forms were observed as additional indicators of their reaction to variable water conditions. The plant material for this study consisted of spring barley breeding lines in generations F₆-F₇ evaluated at 7 locations in 1996-2001. The highest yield was observed with precipitation within the range 258-321 or 356-382 mm per growing season in years with colder or warm weather, respectively. These results were obtained using abundant plant material highly differentiated genetically, so it may be inferred that the above values are the rainfall levels optimal for spring barley cultivation under Polish climatic conditions. The experimental locations could be divided into four classes according to observations on mean yields and on total rainfall before heading and between heading and full maturity. the optimal class included locations where the highest yield was observed; in the second there was a high precipitation level but a lower yield was obtained; in the third class there was a shortage of rainfall before heading, and in the fourth class there was a shortage of rainfall between heading and maturity. The observation of yields lower than those obtained in optimal locations led to the assumption that stress factors at these locations did not allow the yield potential of the studied genotypes to be fully expressed. The studied genotypes showed good adaptation to the variable conditions of the Polish climate, which is characterized by periods with a shortage or excess of rainfall.

Kísérleti munkánk célja volt, hogy műtrágyázási tartamkísérletben vizsgáljuk a N-, P- és K-ellátottság hatását a lóbab szárazanyag-felhalmozására és tápelemfelvételére. A műtrágyázási tartamkísérletet 1989-ben állítottuk be mélyben karbonátos csernozjom réti talajon, 4-4 N-, P- és K-ellátottsági szinten, teljes kezelés-kombinációban, 64 kezeléssel. A tápelem-felvételi vizsgálatokra 15 kezelést választottunk ki. Jelen dolgozatban a 2001. évi kísérlet eredményei szerepelnek, melyek alábbiakban foglalhatók össze:

A lóbab tenyészidejének első felében a 60. napig, a virágzás-hüvelyképződés kezdetéig a szárazanyag-felhalmozás mérsékelt ütemű, az összes biomassza tömegnek 26%-a halmozódik fel. Az intenzív szárazanyag beépülés a hüvely és magképződés időszakára esik, és a tenyészidő 90. napján a levél + szár tömege eléri maximumát (2,25 t ha⁻¹), és a hüvely + mag tömege (2,64 t ha⁻¹) az összes szárazanyag-termésből 54%-ban részesedik. A teljes érés fázisában, a tenyészidő 115. napján a maximális földfeletti szárazanyag-tömegből (5,72 t ha⁻¹) a mag 54%- ban (3,07 t ha⁻¹), a levél + szár 30%-ban (1,69 t ha⁻¹) és a hüvely 16%-ban (0,96 t ha⁻¹) részesedik.

A tenyészidő 35. napján, a lóbab 5-6 leveles fejlettségében a legnagyobb a leveles szár makro elem koncentrációja, ami a teljes érésig fokozatosan csökken. A hüvelytermésben a N-, P-, K- és Mg-koncentráció ugyancsak hígulást mutat, míg a Na és Ca esetében koncentráció növekedés tapasztalható. A növényi részek között N-ben és P-ban a mag a leggazdagabb. A magba több K épül be, mint a leveles szárba, míg Mg-ból kevesebb. A leveles szár Cu- és Fe-tartalma a teljes érésben a legnagyobb, míg a Zn- és Mn-koncentráció a tenyészidő alatt fokozatosan csökken. A Cu és a Zn elsősorban a magban koncentrálódik, míg a Mn és a Fe a leveles szárban.

A lóbab összes N- és P-felvételének maximumát a tenyészidő végén, a teljes érésben éri el. A növénybe épült összes K, Na, Ca és Mg mennyisége a hüvelytelítődés-magképződés időszakában tetőzik, majd a teljes érésig csökken. A lóbab által felvett összes makro elemből a magban halmozódik fel a N 83%-a, a P 82%-a, a K 45%-a, a Na 8 %-a, a Ca 10 %-a és a Mg 48%-a. A leveles szárban pedig a N 7%-a, a P 12%-a, a K 21%-a, a Na 66%-a, a Ca 82%-a és a Mg 33%-a.

A teljes érésben végzett tápelem-felvételi vizsgálatok alapján a lóbab fajlagos elemfelvétele 1 tonna magterméshez a hozzátartozó mellékterméssel együtt a következő: N 61,8 kg, P 9,6 kg (P₂O₅ 22,0 kg), K 22,0 kg (K₂O 26,4 kg), Na 5,1 kg (Na₂O 6,9 kg), Ca 5,8 kg (CaO 8,1 kg); Mg 3,4 kg (MgO 5,7 kg) ; Cu 15 g, Zn 75 g, Mn 50 és Fe 374 g.

Accurate prediction of insect development and emergence is essential for effective pest management, but can be quite challenging. Pesticide application must be timed precisely to maximize effectiveness and minimize the number required. Temperature-dependent development of the cotton whitefly, Bemisia tabaci, B biotype was examined on two host plants (cotton and eggplant) at three temperatures (20 °C, 25 °C, and 35 °C). Developmental rate was faster on eggplant than cotton, however it did not alter for egg and pupal stages on both hosts, but for nymphal stage it did. The statistically estimated lower developmental threshold (T0) for the total development (egg — adult) of B. tabaci was 11.94 °C and 12.33 °C on cotton and eggplant, respectively. Based on lower threshold estimation, the average heat units (dd’s) required for total development on cotton and eggplant were 299.1 and 313.3, respectively. Field data obtained from both leaf samples and yellow sticky traps for each host plant during growing seasons 2012 and 2013 were linked to lab estimation of heat units. Daily heat units (i.e., 299.1 and 313.3 dd’s) were accumulatively counted to test their accuracy in matching the field peaks of the target pest as a predictive tool. On both host plants, our estimation for thermal units (degree-days) from lab estimation is adjusted that of field populations with deviation ranged from zero to four days either before or after the apex. However, there were some false estimations which did not intersect with the peaks of abundance. This may be because the overlapping generations sometimes creates false peaks. The accumulative counts of thermal units were more correlated to yellow sticky trap catches than leaf sample data. Accordingly, degree-days could be recommended to use as a predictive tool for Bemisia flight activity in the field.

There are millions of acres of chemically contaminated lands on which biofuel crops can be planted for dual purposes of biomass production and land reclamation. Phytoremediation is a proven technology for environmental cleanup, particularly in tropical and sub-tropical environments. There are advantages in that multiple growing seasons and increased soil temperature accelerate the clean-up processes. Seeds of 13 tropical and temperate plant species were germinated and grown for 10 days in petroleum contaminated soil containing 3148 μg/g of polycyclic aromatic hydrocarbons (PAHs). The results indicate that the presence of PAHs enhanced both emergence and early seedling growth with some of the species tested. Kiawe tree germination rate was 7-fold higher in PAH soils than that in the control media. The potential biofuel grasses sugarcane, banagrass, switch grass, vetiver and miscanthus showed degradation of PAHs in at least one of the amended PAH-contaminated soils in 35 days of growth. Banagrass biomass production in all the treatments was far greater than the other four species. No plant control pots were most effective to reduce PAHs in the un-amended PAH soil. Vetiver degraded all PAHs when planted in the PAH soil amended with 1/3 of the Promix soil (a 2/3 PAH soil volume). Among five biofuel crops tested, banagrass produced a tripled amount or more of biomass than all the other species in the LF-14 un-amended PAH soil or its amended soils. The dry weight (dw) biomass of banagrass averaged ∼3 g/day/3-L pot in all PAH soils and 6 g/day/3-L pot in Promix as harvested at the ground level. Banagrass in 90-cm spacing could produce approximately 30 tons/ha/yr of dry matter in a 70-day crop season. The results warrant further investigation of biofuel crops for phytoremediation and biomass production purposes. Future plantings may be considered using these and other crops in combination with applicable contaminants to help clean up the contaminated environment and reduce petroleum dependency.

Prior to the field release of natural enemies in biocontrol programs, it is essential to evaluate their efficiency under laboratory conditions. One of the most informative methods is studying the functional response of natural enemy. Moreover, temperature is an important factor that affects the efficiency of biocontrol agent. Firstly, this study examined the effect of host density of the diaspidid insect, Diaspidiotus perniciosus (Comstock) on functional response of the aphelinid parasitoids, Encarsia perniciosi (Tower) and Encarsia citrina Craw (cf. Ben-Dov. et al., 2012 in ScaleNet). Secondly, based on the obtained results from the first experiment, we evaluated the temperature-dependent functional response only for E. perniciosi. Three constant temperatures (15, 20, and 25 °C) and five host densities (10, 15, 20, 25, and 30 2^nd instar) were used. At each densitytemperature combination, a female E. perniciosi (48 h old) was released for a 24 h. In the first experiment, the decelerating rate of decrease in the parasitism rate of E. perniciosi indicated a type II response, whereas the absence of significant dependence on host density by E. citrina indicated a type I response. In the second experiment, the daily rate of oviposition per female of E. perniciosi was significantly increased when temperature and host density increased, however, the type of response (i.e. type II) did not alter with increasing temperature. The attack rate for E. perniciosi increased with increasing temperatures from 15 to 25 °C, whereas the handling time decreased. The 25 °C seems to be the most suitable condition for Encarsia activity and reproduction. This implies that E. perniciosi is well adapted to relatively moderate temperature, which allows its implementation as a biocontrol agent against D. perniciosus during the growing season even in countries of higher latitudes.