Sugar beet profits from intercropping with wheat both under optimum and deficient phosphorus supply | SLADKORNA PESA USPEVA BOLJE KOT PŠENICA V MEDSETVI V RAZMERAH OPTIMALNE IN POMANKLJIVE PRESKRBE S FOSFORJEM

English. An experiment was conducted with wheat and sugar beet as monocrop and intercrop under low or adequate phosphorus supply. Dry matter production of shoot and roots were decreased in wheat while increased in sugar beet under intercrop conditions. Photosynthesis rate was diminished under intercrop conditions in wheat while elevated in sugar beet concomitant with reduction of transpiration rate and higher water use efficiency in the latter species. Phosphorus, potassium and iron contents were also lower in intercrop wheat while increased in sugar beet. The same effect of intercropping on biomass and nutrients uptake was observed in the short term hydroponic experiment. Interestingly, three root parameters including length, soluble carbohydrates and activity of secretory acid phosphatase that are characteristics for phosphorus-deficient plants were enhanced in both species by intercropping irrespective the phosphorus supply level. These data suggested an interspecific interaction beyond the different nutrient acquisition capacity in the intercrop pots.

Slovenian. V raziskavi je bil opravljen poskus s pšenico in sladkorno peso v čisti kulturi in medsetvi v razmerah primerne in pomankljive preskrbe s fosforjem. V razmerah medsetve sta se biomasi korenin in poganjkov zmanšali pri pšenici a povečali pri sladkorni pesi. Podobno se je pri pšenici v medsetvi zmanjšala fotosinteza in povečala pri sladkorni pesi s hkratnim zmanjšanjem transpiracije in večjo učinkovitostjo izrabe vode. Pravtako so bile vsebnost fosforja, kalija in železa manjše pri pšenici v medsetvi in večje pri sladkorni pesi. Podoben učinek medsetve na biomaso in vsebnost hranil je bil opazen v kratkotrajnem hidroponskem poskusu. Zanimivo je, da so se neglede na preskrbo s fosforjem v medsetvi pri obeh vrstah povečali parametri korenin kot so njihova dolžina, vsebnost topnih ogljikovih hidratov in aktivnost izločenih kislih fosfataz, kar je značilnost rastlin, ki rastejo v pomanjkanju fosforja. Podatki nakazujejo na medvrstne interakcije, ki presegajo razlike v sposobnosti privzema hranil v lončnem poskusu z medsetvijo.