The growth of rocket Diplotaxis tenuifolia (L.) DC. profiles was studied during 30 days of growing in the chamber under different lighting regimes; T5_ peak at 630 nm, LED1_ peak at 545 nm and LED2_ ...peak at 599 nm. There were no significant differences in dry weight after 15 days, however, from day 15 to 30, the increase in dry weight was significantly biggest under LED2. This agrees well with estimated average leaf area (LA) per plant (43.83 cm2 ), the increase of LA (39.70 cm2 ) and total fresh weight (7.898 g per plant). The regression analysis revealed the strongest correlation between the dry weight and PPFD_R light intensity (0.792**), showing the positive effect of additional LED lighting in comparison with standard T5 light.
Potencijali rasta rukole Diplotaxis tenuifolia (L.) DC. proučavani su tijekom 30 dana uzgoja u komori pri različitim režimima osvjetljenja; T5_ max 630 nm, LED1_ max 545 nm i LED2_max 599 nm. Nije bilo značajnih razlika u suhoj težini nakon 15 dana, međutim, od 15. do 30. dana, povećanje suhe težine bilo je značajno najveće pod LED2. Dobro se slaže s procijenjenom prosječnom površinom lista (LA) po biljci (43,83 cm2 ), te povećanjem LA (39,70 cm2 ) i ukupnom svježom masom (7,898 g po biljci). Regresijskom analizom utvrđena je najjača korelacija između suhe težine i intenziteta svjetla PPFD_R (0,792**), što pokazuje pozitivan učinak dodatne LED rasvjete u usporedbi sa standardnim T5 svjetlom.
In this study, the growth and glucosinolate (GSL) profiles of rocket salad Eruca sativa (Mill.) and Diplotaxis tenuifolia (L.) DC. were determined during 30 days growing under different lighting ...regimes; T5_ peak at 545 nm, LED1_ peak at 631 nm and LED2_ peak at 598 nm. The biggest increase of dry weight (DW) was measured in E. sativa under T5 (0.657 g DW/plant) and the lowest in D. tenuifolia under LED1 (0.080 g DW/plant). GSL content was found to vary significantly, regardless of the light treatment, but it is related with genotype (E. sativa, r = 0.802**). On average, the highest amount of 4-methylsulfinylbutyl-GSL (glucosativin) (7.3248 mg/g DW) was quantified in E. sativa and D. tenuifolia (6.7428 mg/g DW) under the T5. The regression analysis between different light wavelengths and glucosinolates showed the strongest correlation between photosynthetic photon flux density (PPFD_B) and 4-methylthiobutyl-GSL (glucoerucin) in E. sativa (r = 0.698*) and D. tenuifolia (r = 0.693*), respectively, which indicates the effect of light on the response of plants to induced stress and changes in GSL biosynthesis.
In the process of applying a plant protection product mixed with water (spray mixture) at the prescribed concentration with conventional sprayers for chemical protection of tree canopies in an ...orchard, standard models are used to express the dose rate of the plant protection product. Characteristic properties of the tree canopy in an orchard are not taken into consideration. Such models result in fixed quantities of spray mixture being sprayed through individual nozzles into a tree canopy. In this research work, an autonomous system is presented, which ensures a controlled quantity of spray mixture sprayed through the nozzles onto different tree canopy segments. The autonomous system is based on a fuzzy logic system (FLS) that includes information about the estimated leaf area to ensure more appropriate control of the spray mixture. An integral part of the FLS is a fuzzy logic controller for three electromagnetic valves operating in the pulse width mode and installed on the axial sprayer prototype. The results showed that, with the FLS, it was possible to control the quantity of spray mixture in the specific range depending on the estimated value of the leaf area, with a quantitative spray mixture average saving of 17.92%. For the phenological growth stage BBCH 91, this method represents a powerful tool for reducing the quantity of spray mixture for plant protection in the future.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Autonomous modular system mounted on a conventional (CON) sprayer operating on the principle of pulse-width modulation (PWM) control of electromagnetic valves represents state-of-the-art technology ...for implementation controlled application of spray mixture without changing the operating parameters of the sprayer (e.g. spray pressure, nozzle size). In accordance with the principles of precision viticulture, the pulse width modulation control is the primary technology, which allows the application of the required amount of spray mixture exclusively to the target areas of the vine without changing the droplet size spectrum and allows for even deposit quality and reducing the drift outside the target areas. In the vineyard, we tested an autonomous axial sprayer prototype throughout the entire spraying season in 2021 on which we have installed an autonomous modular system with enabled pulse-width control. We tested two modes of operation of the sprayer prototype, namely autonomous (continuous duty cycle control (DC: 0 to 100%)) and conventional (nozzle fully open at all time), at a steady spray speed of 6 kmh-1. We compared the amount of PPP expressed as a percentage between autonomous and conventional mode of operation of the sprayer through individual nozzles on the sprayer. The maximum saving of the spray mixture of 69.8%, through an individual nozzle was measured at phenological stage of the vine BBCH 55. A comparative analysis between the CON and PWM mode of the spray mixture application showed that we saved 626.24 l per year in the automated mode of operation.
Autonomni modularni sustav postavljen na konvencionalnu (CON) prskalicu, koji operira na principu kontrole elektromagnetskih ventila modulacijom širine impulsa (PWM), predstavlja najsuvremeniju tehnologiju za provedbu kontrolirane primjene mješavine za prskanje bez promjene operativnih parametara prskalice (npr. pritisak prskanja, veličina mlaznice). U skladu s principima precizne vitikulture, kontrola modulacijom širine impulsa je primarna tehnologija, koja omogućava primjenu potrebne količine mješavine za prskanje isključivo na ciljana područja vinove loze, bez mijenjanja spektra veličine kapi, te omogućava ujednačenu kvalitetu nanosa i smanjenje zanošenja van ciljanih područja. U vinogradu je kroz cijelu sezonu prskanja u 2021. testiran prototip autonomne aksijalne prskalice, na koji je bio instaliran autonomni modularni sustav s omogućenom kontrolom širine impulsa. Testirana su dva načina rada prototipa prskalice, autonomni (kontinuirana kontrola radnog ciklusa (DC: 0 to 100%)) i konvencionalni (mlaznica potpuno otvorena sve vrijeme), pri standardnoj brzini prskanja od 6 kmh-1. Usporedili smo količinu sredstva za zaštitu bilja izraženu kao postotak između autonomnog i konvencionalnog načina rada prskalice kroz individualne mlaznice prskalice. Maksimalna ušteda mješavine za prskanje od 69,8%, kroz individualnu mlaznicu izmjerena je u fenološkoj fazi vinove loze BBCH 55. Komparativna analiza između CON i PWM načina primjene mješavine za prskanje pokazala je da je s automatiziranim načinom rada u godinu dana ušteđeno 626,24 L.
A novel prototype of a modified centrifugal sheller was evaluated in terms of undamaged kernels, damaged kernels, fragments of kernels and unbroken nuts. Trials were carried out with walnut varieties ...‘Elit’, ‘Franquette’ and ‘G-139’. First, morphological characteristics (fruit height, width, thickness), relative moisture content and walnut shell strength was measured on randomly selected samples. The maximum force was measured at constant weight of dried nuts perpendicular to the longitudinal axis in ‘Elit’ (287.38 ±107.09 N) followed by ‘Franquette’ (223.36 ±101.00 N) and ‘G-139’ (98.08 ±30.76 N). Shelling walnuts with the centrifugal sheller resulted best output in ‘Franquette’ with 78.05% of whole undamaged kernels, 8.76% of damaged kernels and 7.15% of fragments, while 6.05% remains unbroken; ‘Elit’ only 76.42% of whole kernels, 10.02% of damaged kernels, 9.48% of fragments and 4.08% unbroken nuts. ‘G-139’ gave significantly poorer quality with 60.05% of whole kernels, 21.43% of damaged kernels and 13.63% of fragments and 4.89% unbroken nuts. The output of whole kernels yielded by modified centrifugal sheller is in significant correlation with the walnut thickness of particular variety.
This research demonstrates the basic elements of a prototype automated orchard sprayer which delivers pesticide spray selectively with respect to the characteristics of the targets. The density of an ...apple tree canopy was detected by PROWAVE 400EP250 ultrasound sensors controlled by a Cypress PSOC CY8C29466 microcontroller. The ultrasound signal was processed with an embedded computer built around a LPC1343 microcontroller and fed in real time to electro-magnetic valves which open/close spraying nozzles in relation to the canopy structure. The analysis focuses on the detection of appropriate thresholds on 15 cm ultrasound bands, which correspond to maximal response to tree density, and this was selected for accurate spraying guidance. Evaluation of the system was performed in an apple orchard by detecting deposits of tartrazine dye (TD) on apple leaves. The employment of programmable microcontrollers and electro-magnetic valves decreased the amount of spray delivered by up to 48.15%. In contrast, the reduction of TD was only up to 37.7% at some positions within the tree crown and 65.1% in the gaps between trees. For all these reasons, this concept of precise orchard spraying can contribute to a reduction of costs and environmental pollution, while obtaining similar or even better leaf deposits.
Potencijali rasta rukole Diplotaxis tenuifolia (L.) DC. proučavani su tijekom 30 dana uzgoja u komori pri različitim režimima osvjetljenja; T5_ max 630 nm, LED1_ max 545 nm i LED2_max 599 nm. Nije ...bilo značajnih razlika u suhoj težini nakon 15 dana, međutim, od 15. do 30. dana, povećanje suhe težine bilo je značajno najveće pod LED2. Dobro se slaže s procijenjenom prosječnom površinom lista (LA) po biljci (43,83 cm2 ), te povećanjem LA (39,70 cm2 ) i ukupnom svježom masom (7,898 g po biljci). Regresijskom analizom utvrđena je najjača korelacija između suhe težine i intenziteta svjetla PPFD_R (0,792**), što pokazuje pozitivan učinak dodatne LED rasvjete u usporedbi sa standardnim T5 svjetlom.
U intenzivnom uzgoju vinove loze nužno je koristiti suvremenu mehanizaciju kako bi se svi poslovi obavili pravovremeno i kvalitetno uz najmanje moguće troškove. Kako ručna berba zahtijeva između 250 ...– 300 radnih sati ljudskog rada logično je tražiti smanjenje troškova proizvodnje uvođenjem kombajna za berbu. Usprkos početnim problemima s kvalitetom rada početkom 1970-ih godina, mehanizacija berbe grožđa postaje sve prisutnija u vinogradarskim regijama svijeta. Ekonomske prednosti, kontinuirani razvoj strojeva, i konačno međunarodna standardizacija ispitnih metoda za komparativnu procjenu metoda očitavanja, doveli su do svjetskog uspostavljanja mehaniziranog berbe grožđa. U nastavku su predstavljeni preduvjeti ove tehnologije, prednosti i nedostaci, vučenih i samohodnih strojevi kao i neke tehničke inovacije.
The high workload in the grape harvest (250–300 hours) and the connected
limited impact resulted in the first attempts with grape harvesters in the late seventies. Since then, in spite of initial quality problems, the mechanization of grape harvesting has become more and more prevalent
in the wine-growing regions of the world. The economic advantages, the continuous development of the machines and finally also the international standardization of the test methods for the comparative assessment of the reading methods led to a worldwide establishment of mechanized grape harvesting. In the following, the prerequisites for this technology, the pros and cons, towed and self-propelled machines as
well as some technical innovations are presented.
The concept of precision farming is wide, and it is represented with the efficiency achieved with the help of precise RTK (Real Time Kinematic) navigation, digital maps and appropriate software. ...Different studies around the world reported considerable fuel and time saving during soil tillage and seeding which based on omitting the overlapping and the frequency of turning round at the end of fields. For smaller farms, which commonly use 3 m working machines (cultivator, chisels, disc harrow) up to 15.7% of the time and 8.66 % of the fuel can be saved, while on 6 m machines up to 12.6 % of the time and 8.28% of fuel is saved. The main reason lies in the reduction of overlapping width which in manual driving conditions usually represent about 10 % of nominal working width. The use of precision agriculture technologies allows us to better plan and analyze the working procedures.
Koncept precizne poljoprivrede vrlo je širok, a najčešće se pojašnjava povećanom učinkovitošću postignutom pomoću precizne navigacije, digitalnih karata i odgovarajućeg softvera. Različite studije širom svijeta pokazale su znatnu uštedu potrošnje goriva i vremena tijekom obrade i sjetve tla koja se temelji na izostavljanju preklapanja i učestalosti okretanja na kraju polja. Za manje farme, koje obično koriste trometarske radne strojeve (kultivator, gruber, valjari) smanjuje se potrebno radno vrijeme do 15,7% i ušteda goriva do 8,66%, a na strojevima od šest metara do 12,6 % vremena i 8,28% goriva. Glavni razlog je smanjenje širine preklapanja vožnje koja u uvjetima ručne vožnje obično predstavlja od 6,5 do 9,5% nazivne radne širine. Korištenje preciznih poljoprivrednih tehnologija omogućuje također bolje planiranje i analizu radnih postupaka.
U ovom su istraživanju prikazani temeljni principi rada strojeva za mehaničko uništavanje korova (međuredna kultivacija) u kukuruzu i šećernoj repi te kultivacija unutar redova usjeva koja je ...omogućena razvojem različitih prstastih kultivatora. Kako bi se olakšao rad traktoriste i ubrzao radni proces nužna je upotreba senzorskih pomagala bilo na temelju RGB slike te odgovarajućih mikro-kontrolera odnosno u zadnje vrijeme sve dostupnijih autonomnih sustava (RTK-GPS) navođenja strojeva. Za njihovu upotrebu nužna je precizna sadnja istim sustavom te izrada karata pomoću kojih se provodi kultivacija. Pravu budućnost kultivacije kukuruza i šećerne repe predstavlja razvoj i vođenje autonomnih robota za kultivaciju koji u svakom trenutku pomoću bi-spektralnih sustava analize slike te RTK-GPS navođenjem traže i uništavaju korove bez neposredne ljudske kontrole na polju.
PDF
